Thanks for your time and efforts to share your experiences. I'm in the middle of the conversion, and your sharing has saved me much time and probably $$... Tech support should be your handle... Things worthwhile usually take longer than anticipated....
5 months later and my 89 YJ is still running sooo much better than the carb / vacuum mess. Worth the time. Your video's accurately showed all the pitfalls of mine as well. Saved me a lot time / potential frustration, thank you! Found out the previous owner like duct tape as soldering, more time in fixing other things than installing the actual TBI. ha
The kit has worked without a hitch, even as the weather turned colder. Once in a while the RPMs take a few seconds longer than seems necessary to come back to idle when I pull it out of gear (I have a manual) but that's REALLY minor. On your '76 the kit would be even easier to install, except that you might need to weld in the bung for the O2 sensor in your exhaust. Anyway, I have no complaints about the system--it just starts and runs now with no drama.
Great video, I was able to find and buy my cj7 back after 21 yrs . It was converted to a Howell Fuel Injection from carb. Lots of different hands have worked on it prior to me getting it back. I’ve put in a lot of time in getting it to work correctly. I’m kicking myself for not finding your video sooner. I did call Howell tech support more than once and basically got the replace part and if does not work then replace another part , basically I tried the new parts and then when problems did not change, I just put old ones back on. Otherwise I would have been looking at hundreds of dollars of changing parts that were fine. I was finally able to resolve my problem with just very methodical patience and tracing the wires to make sure everyone had a proper connection. It was a simple fix, but it was just very hard to find , not having the experience and knowledge with this system. I do electrician work and lots of trouble shooting on complex line and low voltage for a living . Most of the time the problem boils down to connections or wrong wiring which does take time to figure out. Very rarely do I have to replace a major part or small part. I felt that Howell tech support was very impatient and lacked any helpful advice except replace parts then goodbye seemed to be their motto, was wondering if anyone else has experienced similar problems with Howell tech support.
Funny you mention the lack of support--I also found back when I did this that their support was lacking. The directions they send with the kit are written like a 5th grade book report. The information is there, but what a mess! I even offered to re-write the installation sheets professionally, but that fell on deaf ears. Anyway, if you have issues in the future remember that the system is essentially a Chevy truck from the 90s. You can find lots of diagnostic info online by searching for mid 90s six cylinder Chevy pickup trucks.
Thank you so much for the vid. I pulled the old computer out, and messing with the wires now. I cut "ALL" the wires associated with the bundle to the batter tray, and then your vid showed me I needed the relay for the manifold heater. So i'll be re-solidering, thanx for pointing out the two yellow wires, one will go to the heater manifold, the other is going to be power to the HEI ignition.
It is a tricky thing to trace all these wires and remember what you need and don't need. After you're done it actually makes sense, but in the middle of it the task can be daunting!
I bought it directly from Howell on the theory that they would be more eager to provide support if I bought it from them. It was the same price as in the catalogs. But, I ended up figuring it all out for myself anyway.
tinderboxarts talking to them is a waste of their time and they do their best to infer it. Thanks for the tip on being like 90s Chevy truck set up . Also thanks for getting back to me. Keep up the great videos, who knows maybe you will put their lack support line out of business. I just refer people to your channel if they want to learn about this system
@@jasonlenihan9854 I want one of these systems but they DON'T answer questions via email, I looked at their instructions and they seem complicated, the CONCEPT of all GM proven technology and NOT having to do setups & adjustments on a separate screen box I LOVE ! I pay the price they want and can't get Customer service would be not good advertisement
Its weird that there is duct tape on the factory harness where the wires were spliced together. I had to trim that off and use electrical tape when I did my install. Just didn't seem right to leave it there.
So power to the fuse block doesn't need to be a constant 12v? From the install guide it's a switched source when in the crank and run position only. Tracing the wires from my harness near the fuse block shows 3 fused wires, 1 goes to the ECM and the other 2 go to the injectors. So how does the ECM keep it's memory? Also what colors were your check engine light wires?
Hi again. I just have wiring left. I notice that there were some left oflver wires. Those came from fuse box. Rest where pulled our. Also what air filter assembly did you for assembly on top of f.i
The air cleaner is a tricky factor because if it is too big it will interfere with the brake vacuum booster. I ended up buying an inexpensive ten inch open air filter, which is really just two metal plates sandwiching a 10x3 air filter. Honestly, I thought it would be temporary until I found something better, but it's been on there for years now and I've had no problems.
I admire you making this video and showing how to install this unit. Myself, I would pass this up. The time and effort working on the jeep to update it is not worth it to me, just my thoughts. This is far from a plug and play install, which I know it's not. I would buy another jeep lol.
Well, I installed this fuel injection system ten years ago and the Jeep is still going strong with it. The Jeep has at least doubled in value in that time too. So, yes, there's some effort in getting the EFI installed, but keeping an older vehicle like this on the road often requires some extra effort.
Anthonie Galvan--I'm not sure a follow your question, but I suspect you may have become confused about the directions for your model year. There are differences in the wires that you describe depending on model year. Go back to the Howell directions (linked in the comments here) and double check that you used the right procedure for your model year.
I would love to see more photos of the vacuum line connections after you installed the TBI. I have an 87 YJ (automatic transmission) that I just competed the conversion on. It runs, but I don't think the vacuum lines are hooked up properly. Any help would be greatly appreciated.
Sir, thank you for your efforts. Ten years later and I'm installing this system on my newly acquired 1990 YJ. Howell must have sold thousands of these kits. How have the last ten year been in terms of reliability? Anything you would have done differently today?
Has it been ten years?? Wow, time flies when you are having fun! The kit has been pretty much trouble free. I think I did replace the oxygen sensor at one point because it was not performing correctly. Other than that I can't recall any issues.
my dura spark has a black and white braided line going to it from the distributor. It doesn't match the howell schematic for the duraspark. do i cut and rewire following diagram
I don't think I can answer that remotely over the interweb, but all I can say is don't get too hung up on color coding. Sometimes the wiring is just a different color because someone rewired it or it's a different year than in the directions. Take a step back and trace the function of the wires in question. You should be able to match up the function of each wire in the Jeep and match it to the Howell directions, even if the color is different. If memory serves me, I think the ECM just needs a tach signal from the negative side of the coil.
So I just swapped in this kit and I’m having a sputtering issue that I can’t figure out. It runs and starts but I have this air sucking sound from the intake that with go away after it warms up. It revs fine during the warm up but as soon as it’s warm it backfires out the intake. And if it doesn’t and the hard air sucking sound doesn’t go away it sound like a lawnmower popping out the exhaust
Boy, it could be a number of things based on your description. A vacuum leak comes to mind first. Aside from the vacuum hoses, there is the throttle body itself which I think is supposed to have one port capped off if memory serves. And there is the throttle body gasket which could be leaking. And there is the brake booster vacuum line which may have been disturbed or cracked when you were working. You can get a can of carb cleaner or similar and spray it around these areas with the engine running to see if the RPM changes with the spray. It may be that as the engine heats up and materials expand, the vacuum leak seals itself off. Another possibility is a fault with the throttle body, such as an injector not working properly. But the backfiring you mention muddies the water. That can be associated with a spark timing issue. Maybe you mixed up plug wires when putting things back together?
I am about to attempt the same. 90 Wrangler. I am mechanically incline. but the wiring is the scarry part. How did you handle the Pulse air sytem. Cut and cap the end? where did it end? At exhust? Thank you so much for you video, made it easier for me to make the on the challenge!
The pulse air system just gets removed, and if memory serves you can cap off the port into the catalytic converter either by welding it shut or installing a cap over the pipe stub. Or you could replace the whole cat if it is time anyway. The wiring seems daunting, but just take your time and lay it all out with labels before you make the cuts. Once you start labeling everything the number of wires is cut down and what you need to do becomes more apparent.
@@tinderboxarts Thanks for the response. This was a family wrangler from a family member that died from cancer and it was in bad shape. Rusted out cooling system(pump, Raid, thermo and housing). head gasket was blown. So is a project for few more months. Could not get vacuum right and was really a hard cold start. I talked to local guy that only did jeeps. He said he would not work on these carbs anymore to many issues and Stepper motor is no longer available. I will send pics once i am done. again thanks Juan
That's great you've taken on this project, I'm sure it will be worth it in the end. If it makes you feel better, the switch to throttle body fuel injection is night and day from the old carb. You'll be amazed.
@@tinderboxarts What about the 4 in and 10 in vaccum at the firewall. do we cap those or is it used for something in the inside of the jeep? Juan. Again thanks for you response and help
You're testing my memory now. The only things I can recall are that the 4x4 engagement of the front differential was controlled by vacuum. That mechanism frequently went bad. Like many others, I installed a mechanical cable in it's place. Possibly a heater flap was vacuum controlled. In any case, it's nothing super critical so you could leave it off for now and if you discover something missing add it back later.
Hi there buddy I took my 89 to the mechanic to install this kit and he mounted everything good nice clean job but he messed up the Jeep never worked. It starts but if I let go of the key it turns off I need to hold the key on for it to stay on. Now I can find the dam mechanic and I have no idea what it is , plus he removed the white tags that came with the harness any help will be greatly appreciated thanks
Oh boy. So, normally the key is switched to the start position momentarily to engage the starter, then you let go and it stays in the run position. Are you telling me the key won't stay in the run position? I'm just wondering if your real problem is the ignition switch and it was just coincidence that it broke at the same time you had the Howell system installed.
The switch feels exactly like before the efi. Example first click is instrument panel second is crank and normally it has that little spring tension at the end as soon as I let go of that tension it turns off
The issue now is that the mechanic got rid of the old harness so I don’t know why goes to where I think the problem exists in the switch power but not sure since am not a mechanic if I could see what wire goes where I can probably fix it
@@tinderboxarts hey buddy sorry to bug you again but your the only one with this info in RUclips. So I got my Jeep running and now I took it to emissions test but it fail the guy said is missing the line from the charcoal canister to the fuel tank and is true I don’t see a line connected to that port in the canister but what confuses me is that I only see two metal fuel lines under the Jeep one is my filter and pump and the other one am not sure but it’s also plugged into the back of the tbi and I don’t see any other line that could plug into the canister from the tank ? Any help will be appreciated
@@Divinemindset04 I have to laugh because in New Jersey they don't even inspect vehicles older than 1996 anymore! The fact that your local inspection is actually looking for charcoal canister lines is crazy. Anyway, you are testing my memory a little bit. There should be three lines going to the tank, a fuel line supply, a fuel return, and the charcoal canister. If your canister line is missing you may have several choices. Possibly you replaced the entire fuel supply or return lines with braided line when you did the Howell installation. If you did and the old steel tube is still there you could re-purpose it for the canister. If you still need that for the fuel, then you'll have to look at the tank to see where the canister line would have entered. It's been a long time since I dropped a YJ tank, so I can't remember what it looks like. The way these canisters work is that fuel vapors from the gas tank are basically sucked into the charcoal filter for storage and under certain conditions the engine vacuum is sent to the canister. When that engine vacuum is applied to the canister it supposedly clears out the stored vapors. In more modern cars there is a system which monitors the gas tank pressure and throws a check engine light if it senses a loss in pressure. That's why a loose or leaking gas cap can sometimes cause a check engine light. But, in the old YJ that system doesn't exist. So, about the only thing an inspector could do is visually check for a line between the canister and the tank. Unless he uses a smoke machine or a vacuum tester he'd have no way of knowing for sure if the canister is working. Probably all you need to do is get your head under the tank and look for a port that used to have a hose attached. You can run a rubber hose from that tank port all the way to the canister, or you can put a metal line along the frame rail and use a rubber hose on either end for the connections. The charcoal canister was factory, so there must be a port at the tank somewhere.
hi, we spliced in the supplied purple wire to # 18 purple wire from original module and jumpered #47 & 59 together. i assume this is the signal for injector pulse from distributor, but it does not tie into the howell ecm since the original harness is disconnected, so we have no injector pulse. did you run into the same problem? how does the howel ecm pick up the distributor signal when the original harness is now unplugged?
Hey great vid, it's been 6 years and still very useful!so I'm about to have my 258 rebuilt and once it's done I'll be doing the conversion. My question is the 2 hoses going to the stock air cleaner one being downstream air injection tube port from the cat (gets capped) and the 2nd upstream air injection tube port is coming from the front exhaust pipe right under the connection to the manifold, does that get capped too? Sorry so wordy.. thinking I should be able to get away with just getting a new complete exhaust setup without the 2 ports mentioned above.. thanks for your time and again great vid!
So, the air injection system was an ill-fated design meant to inject oxygen into the exhaust stream and catalytic converter during certain periods. The point was to make the catalytic converter more efficient and to give unburned gases in the exhaust a chance to burn off before exiting. There have been other similar systems which inject air, although not with the confounding valves! With the Howell system you are essentially turning your Jeep fuel system into an early to mid 90s Chevy truck. That entire pulse air system is no longer relevant and you can remove everything. The tube or "port" coming out of the existing catalytic converter can be plugged any way you find convenient and the same goes for the exhaust. When you go to replace that cat when it rusts out or stops doing it's job, you can just insert a universal style without the port and be done with it. A universal cat is actually not that expensive so you may choose to do it from the git-go.
@@tinderboxarts thanks for the input! Wanted to double check before I go ahead and order a new complete exhaust system.. my Jeep has been down for far too long. Did the nutter bypass with the Carter carb that I've had to rebuild a few times.. was going to go with the Weber carb but I'd rather finally have run legit.. thanks again have a great day and stay healthy!! ✌️
You know, most shops are not going to want to tackle something like this at all. They won't want the liability, they are probably unfamiliar with it, and they typically stick to OEM stuff only. You'll have to look for a specialty shop in your area, maybe one that does 4x4 off-road work, or one that builds hotrods or restomods. It wouldn't be cheap. If this is beyond your skillset to do yourself then your better bet is probably to find a friend who works on cars to help.
About to do this conversion on my 90 yj. Was wondering if any special tools are needed or would help in this job. I have done a lot of basic work on it over the years, but this would be the biggest job yet. Would love some pointers to help me along. Love the video
Caleb Smith Standard electrical and automotive tools are all you'll need. One exception may be an electric soldering iron used to "tin" the ends of wires or to solder two wires together. When the installation called for joining new wires to the old harness I soldered the two wires together and covered them with shrink-wrap insulation. There are mechanical connectors you could use instead, but they tend to corrode or come apart over time. Other than that, just take the time to pull the harness out and apart so that you have everything out in front of you in the engine bay. The first cuts are psychologically difficult, but after that it get's easier! The fuel pump installation may take a little more time then you think, but just take it one step at a time and it will all come together.
Question? What wiring did you use for the supplied fuse box? Will one of the switched yellow wires left from the ecm removal work that is switched power? Also I didn't run the manifold heater relay wire. I never had the green wire coming from my manifold so I just reconnected the wire that it originally had I also went through allthe wires and never saw it being affected by wire removal.. I used your video for guidance thanks, Also my manual said to connect the vacuum from port A off the howell tbi , you used J? Do you think it matters? The other one I capped.
Different year Jeeps can have different options and connections, so yours may vary. It's been too long for me to remember wire colors! Your Jeep could be older and doesn't have the manifold heater.
I'm currently doing this install on my 89 Wrangler and have a question for you. The PO of this jeep had the gas tank vent hose removed from the canister to the tank. The instructions say to hook up your return line from the throttle body to the line previously used to vent gas vapors to the tank. This is where my confusion is. I currently have 2 gas tank lines that I need to hook up and I'm thinking the smaller line on top of the frame rail which is the tank vent line is supposed to go to the canister and the line underneath the supply line hooks directly into the return port of the TBI. I've tried contacting Howell to make sure this is correct but have gotten no response, hoping you can help! Instructions aren't written clearly for someone who's never done the install. Thanks. Your video has helped a lot.
I just went out to look for you. You've got two fuel lines, one for the supply and one for the return. Then there is a small vapor line which is steel along the frame rail, which changes to rubber for a foot or so before it enters the canister. Look at the video and freeze it at 22:56. You'll see two T vacuum fittings. The top one is your answer. It has one line leading from the top of the valve cover to the left side of the T, it has the canister line on the right side of the T, and you can see where it enters the throttle body. I think that should answer your question.
Do you remember which wire you used for the crank and run 12V source for the CPU? Did you use the 'start' (green wire) for that, or did you even end up using that one?
On the ignition module,the fourth wire that you added to the plug we’re does it go? I got lost there, you pink wire , what does that pink wire control?
I don't yet! It has continued to run well and it has a nice growl to the intake when you romp on it! When the temp gets below 20 degrees it sometimes runs slightly rough for about 15-30 seconds, but I think that may be a bad intake heater on my Jeep.
Hey tinderboxarts! I'm back... :) I've finally converted my cj7 to the gm tbi... But the ecm is flashing the codes: 42 and 43.. Meaning it has no spark control.. --I guess because I DIDN'T install it.. Any suggestions on how to make it go away OR what distributor to get to allow the ecm to control it? I've already tried to connect the b7 to c11 to fool the computer.. But the check engine light still illuminates and runs like a dog... :(
I think code 43 might be the knock sensor. Did you install that? If the CJ7 doesn't have a place to bolt that on you may need to fabricate something. At the very least, connect the wire to the sensor and leave it hanging somewhere. Code 42 I think may relate to the tach signal for the computer. Did you connect or splice the tach wire to the tach signal from the distributor? Even your old CJ will have that, although you'll have to look up which wire it is. Without the tach signal your computer will be in "limp home" mode because it has no idea of engine RPM.
No. I didn't install the knock sensor. Do you know if I also have to install a distributor that will allow the ecm to control the timing? I installed the tach wire to the "-" side of the coil. :o
rag Doll No, the ECM just controls fuel. It will work with pretty much any distributor. There is a special note about MSD ignitions, though: "NOTE: Multiple spark discharge ignitions require a special Tach filter to function correctly. Contact Howell Engine Developments if you need one." Of course, the problem could be a bad ground or a voltage drop from a poor wire connection. Take things one step at a time to find the issue. And, you'll have to rig up something for the knock sensor. I think I show in my video where it is supposed to go.
I should have said that I didn't get the Howell kit... Instead, I bought a reman ecm and gm tbi... ") Therefore the ecm is complaining that it doesn't have spark control. I've read I could have the eprom chip reprogramed so that it only controls the fuel, like Howell kits. But I really would like to have it control spark/timing. Also, I ran the ground wire from the intake directly to the negative battery terminal, so there shouldn't be any ground issues. AND I installed a separate 12volt wire directly from the harness (with fuse of course) and the ignition coil positive side... So, both of those should be fine.. ;) Thanks for your suggestions. I've contacted Howell and affordable and neither have responded to my emails. :0 Next, I plan on calling them. :)
+rag Doll Did you get your spark timing sorted out I am doing the same swap you did and thinking of using the gm hei dist so spark timming is left out of the puter
Where can I find a dual cto valve? I have a 89 yj and have the same configuration under the hood, and same Howell conversion kit. I stumbled across this half way through the conversion, my cto valve is toast, and I'm having the hardest time finding one. I can't find one anywhere.
They are right under your nose! Only Jeep calls it a CTO valve--everybody else calls them a ported vacuum switch. You can pick one up from Amazon: www.amazon.com/gp/product/B000C83RF0/ref=oh_details_o08_s00_i00?ie=UTF8&psc=1
I have a 90 Wrangler YJ and I'm installing the CARB Howell kit right now. My thermal air cleaner has a 2 inch duct tube that goes to the exhaust manifold and I'm assuming yours did too. What did you use to cover the outlet hole on the exhaust manifold after the conversion?
Do you mean the hot air duct from the manifold to the air cleaner? That's designed to help during cold-start up by sucking air past the manifold, which heats up quickly. On the manifold is just a little sheet metal receptor for the duct tube. There is no actual hole in the manifold, or if you have one there is a problem! You can just leave the duct tube off if you're using an open air cleaner with the Howell system and the sheet metal on the manifold can stay where it is.
Great vid, I'm swapping my engine in a couple of weeks, slowly getting parts together that are more robust rather than reuse. I put a weber carb on last year. it helped (sort of) but I'm going to do the howell with the new 258. question though.did you swap out any ignition? I did the nutter, but would't start so shifted back. I was thinking of doing a different distributor and coil.
STEPHEN PORTER Yes, I did change the ignition many years earlier. I can't recall the maker of the ignition coil, but it was a more powerful unit based on the Ford TFI. As you probably know, the Ford TFI system from a 1981 Ford F150 truck will swap in (1978-1990 Jeeps), which gives you a more robust cap and rotor, the more powerful coil, and wires to match. It was well worth the minimal investment and has been easy to maintain.
Okay then I had a question I'm ready to turn on the jeep but when I go to crank the jeep over the fuel pump gets no power but when i do click the switch on I do hear it come on for a few seconds but when I go to crank it loses all power
Manuel Hernandez I can't give you too much advice from memory, but it sounds like you may have either crossed a wire or missed a wire. You need power to the pump with the key on, obviously. Go back and sort through all the wires to make sure you didn't miss one or pull power for the pump from the wrong source. Those Howell instructions are badly written but all the information is there if you search through it.
Great Video! I picked up a 90 yj and the guy I bought it from did the conversion. It runs rich and I have not been able to figure out why. Any ideas? I thinking it has something to do with how the Vacuum lines were hooked back up (or not). The Howell instructions are not good with diagramming them. Can you tell me how I would know if they are all run correctly?
Coincidentally, I just recently noticed mine seemed to be running a little rich too! I haven't had a chance to investigate yet. Keep in mind this system is basically identical to a 90s vintage Chevy truck. Everything that applies to those fuel systems applies to the Howell Jeep version. So, there are a bunch or sensors that tell the computer how to adjust the fuel/air ration via the throttle body injectors. The O2 sensor is one obvious place to start, since that attempts to measure the exhaust of the engine for oxygen so the computer knows if it is rich or lean. The MAP sensor is another place to look. There is a temperature sensor to tell the computer when the engine is at operating temp, and if that goes bad the computer will stay in a warm up mode that is too rich. Even a faulty throttle position sensor can trick the computer into a poor fuel mix. So, I would first check out all the sensors for proper operation, and there is loads of info on how to do that if you look under 90s chevy trucks with TBI. A complete check only takes 30 minutes if you have a multimeter and the specs at hand. I doubt the vacuum lines are your issue.
tinderboxarts thanks for the reply. I do have a multimeter. Where is a good place to look for the specs? Are they the same for a yj as they are for a truck?
You can download the Howell install directions if you haven't already, and somewhere in there they list the actual components and manufacturer model numbers. But, this is all pretty vanilla Chevy truck stuff, so you can get the info from Chevy sources (I hesitate to post links here since they may disappear later). I mean, the O2 sensor is a single wire model that will vary between 0 an 1 volts in operation. Just look up on the interweb how to test a single wire O2 sensor and the generic instructions will work. Same with the MAP sensor testing--just look up the generic directions. If a buddy or the library has a Chiltons manual for a mid 90s Chevy truck, the component tests shown there will also be valid.
So, just wanted to circle back on this. I contacted Howell after the sensors all checked out OK. They want me to check the fuel pressure (should be between 11-12 psi). Im not sure how this could be causing my issue, but willing to give it a shot. Any idea if too much or too little pressure would cause it to run really rough when first started in cold weather and then be OK with the engine warms?
Wasn't your original problem that it ran rich? The rough cold start issue is a little different. Fuel pressure is basically good or it isn't good, meaning that the system needs enough pressure to do it's designed job and it also needs enough volume. If there isn't enough pressure or volume it usually means the engine will run very poorly or not at all. Yes, it is possible for the pump to be providing marginal pressure or volume and the computer tries to make up as best it can for the issue, but I don't think this scenario is all that common. It can't hurt to test the fuel pressure, but what you are describing now is a rough running engine at cold weather start up and smooth performance when the engine comes up to operating temperature. In the old days when you had a carburetor the choke took care of this problem by providing a richer mix during warmup by constricting air intake. With computer controlled fuel injection, the computer provided the same function by enriching the mix for a period of time or until the temperature sensor tells the computer the engine is warmed up. So, again, the computer relies on the sensors and the wiring to the sensors to be accurate in it's programs. Now, if you are running rough only during the period when the engine is cold, it seems likely that the mix is leaner than it should be. Assuming that the fuel pump is providing enough gas and assuming the sensors AND the wiring to the sensors is good, then a vacuum leak could be another culprit. There are two old school tricks for testing this. One is to use a can of carb cleaner and spray it heavily around each of the vacuum hose connections while the engine is running. If there is a leak, the RPM will dip when you spray heavily by the leak. Don't forget to spray around the base of the throttle body, where the gasket itself can cause a vacuum leak. The other trick is to use a pair of needle nose pliers to squeeze off each of the vacuum hoses to see if the RPMs change. Since testing for a vacuum leak is quick and easy, you may choose to do this first before moving on to more esoteric issues.
Hello, May I ask you for an update? How has it ran for you since then? Do you have to smog your vehicle in your state? I am just about ready to go get inspected......scouring the internet for info on what to do with the pulse tube....I see you capped it off, but I might need it for smog.....it is used to get the cat hot enough to start working.... Anyway, I just wanted to say thank you for sharing you video. I seen it several times years ago before buying my kit, and now came back again for reference.....good video ;)
It's still working well. I did just replace the o2 sensor, which was defective. The one supplied is not very good quality. Other than that I've had to do nothing. It did pass my NJ inspection previously, but now NJ has changed the law and anything older than 1996 is exempt anyway. If you're worried about the cat, you can source a different universal style which will not have the tube.
So I'm also doing this on a 90 yj. How long did it take. I live in California what else was needed to be done to pass smog? A new cat? Any info regarding smog would be much appreciated.
I have zero knowledge of CA inspection requirements. Here in Jersey they don't even inspect cars older than 1996 anymore! However, Howell does sell a CA specific kit, I believe, and they do provide a new sticker for the Jeep to indicate the upgrade. It shouldn't be a problem and I would suspect you'll be fine. The catalytic converter wouldn't need upgrading unless you coincidentally have an older one that has failed. As far as timeframe, that really depends on your knowledge, confidence and tools, as well as the condition of your Jeep. You may end up fixing other things along the way if your Jeep is in ragged shape. If you are reasonably knowledgeable you'll get most or all of it done in a weekend, but it may take longer to deal with rusty bolts or things breaking off in your hands--the usual!
Awesome vid, thank you. I'm mid install and this video has been the most helpful thing so far. Quick question. The two pin connector on your duraspark ignition, does it plug into a plug with green and yellow wires? Mine have red and white going from ignition to plug, but I can't remember what plug went back in. (I took a *long* break during this install)
I was able to figure out my issue. Thank you! I'm just having an issue with the ignition coil now (passenger side). The white tach wire is supposed to go in the same spot as a green/white already there. I'll probably just splice.
Thank you for making this video! I'm in the middle of the instal and making a royal mess with the wiring After. watching you struggle with the wiring harness off the computer, I just quit and left it! I did cut the wires off the diagnostic port by the battery and was trying to walk them back. I hope and pray I didn't cut anything I need in the future, cause I didn't mark a thing. (I know, rookie move but I was feeling brave and stupid) Did you ever go back and clean up the harness? Are you still a fan of this upgrade after all this time. - I still have to find a way to plug the pulse air connections of the exhaust manifold and CAT. I'm telling you I made a mess hahah, but almost done!
Yes, I'm still glad I made the effort and it has worked well for me. I did clean up the harness and put everything back together neatly. Just take your time and take it step by step.
***** Yes, I still have the same Jeep and the Howell system is still going strong. I've got plenty of OTHER issues, of course! ;)This winter it got very cold in my area, but the Jeep started every time. The "choke" for the Howell system seems to take 30 seconds to set the RPM correctly, but it never stalls or fails to start even down to zero degrees. It was definitely worth the effort to install.
Nice Video. It'll definitely help with my install that I'm planning this summer. Right now I've swapped mine to a Motorcraft 2150 Carb. It runs really well but I live In Cali and the smog dogs are upon me so the swap makes sense. Now my questions. Did you see any increase in mileage? How about power? Sure would be nice to see and hear it run... Thanks for the Vid...
At first my mileage seemed the same (about 15 MPG) but my last tank was 20MPG. It might have something to do with the gas formulation here in the winter. I passed NJ emissions without problem. The power is not dramatically different, I guess, but it feels more consistent throughout the entire RPM range. With the original carb it would hit a flat spot around 2200 RPM. Now it pulls steady right through to the higher RPM ranges. My only complaint is that in single digit ambient temps it takes 30 seconds for the computer to really kick in the "choke" function. It still starts and runs fine in those temps, though.
please please help me. this morning it started for a few seconds then it stalled. doesnt want to turn on anymore it just cranks and cranks as if it had a kill switch or something(it doesnt). injectors dropped a few drops but not a spray like it used to. just a drop here and there. the distributor works i know cause i got a nice shock all over my body.lol it was pretty refreshing but i wasnt ready for it. i didnt do the conversion. i just bought it and it didnt do that after 2 days of test drive
You need to go through all the systems methodically. Does it have spark at the spark plugs? Does it have fuel pressure and volume? Is there compression? Do you have a problem with a sensor like the crank position sensor? You must eliminate each system as the cause one by one or else you're just chasing your tail.
You posted 2013 HOW is it functioning now? ANY issues? I'm considering this setup for my 302 AOD 1965 F100, the ONLY thing keeping me from it is what appears to be unclear instructions
It continues to run strong, although I'm just starting to notice a little stumble that I suspect is the EGR valve. It's all common stuff available off the shelf, though, so no worries. I've been very happy with the setup.
@@tinderboxarts Thank you for your response, now considering the kit for a current FI 94 F150 300 inline 6 , want to get rid of the crap Ford system, is yours STILL running good? Did you ever have to actually talk to them for help??? Your experience with that issue??
@@REVNUMANEWBERN Still running! I think I replaced the oxygen sensor last year, no big deal. I've never contacted Howell so I can't say how their support is, but these are all off-the-shelf components that you can buy in parts stores.
Hi again, Thanks for your review and upate. I updated my intake manifold with an 1985 intake and a new exhaust manifold that already has the O2 sensor port. Does Howell offer a Throttle Body with a kickdown/passing gear bracket? (I have a TH400 auto trany behind my 258. Am I correct to say rhe ECM is pre-programed and is NOT a ;earning computer? Did you have to do any throttle body adustments or is it plug and play? Also, I don't have a computer/brain in my cj7.. Hopefully it will be easy. Thanks :)
Interesting question on the kickdown for the auto trans. It doesn't come with one but I'm sure you could rig up the existing linkage pretty easily. The computer and TBI are plug and play--get the wiring and sensors right, and they'll just work!
So, check the coil. Put an ohmmeter on the primary and secondary windings and look for a short. A primary winding has a resistance typically in the area of .5 to as much as 2-3 ohms. The secondary could be in the neighborhood of 5000-20,000 ohms. Zero resistance is an internal short and a very high resistance is an open winding. Different designs will have different specs. On my Jeep I replaced the coil with an aftermarket version, which you may have too.
+G. oAway Sorry for the late reply, I missed your comment. My mileage is not in that range and I suspect that kind of range is unlikely for anyone except under the most ideal circumstances. 16-17 MPG is probably more realistic and if you are doing spirited driving (who, me?) then 14-15 MPG. I am still happy with the system, though. It has continued to be reliable under all conditions and it never fails to start on the first try. I'll be adding a minor lift and larger tires shortly and I'll be curious to see how the Howell system handles the different final drive ratio created by the larger tires.
The temp gauge on the dash and the temperature sensor for the computer are two different things if I remember correctly. Maybe you accidentally dislodged the wire for the gauge (I think it's on the top toward the back of the engine) when you were working?
Salut, bien cette vidéo mais il aurait été sage dans ton explication de montage d'expliquer un peut plus les branchements électriques, a savoir quoi va ou !!!
Thanks for your time and efforts to share your experiences. I'm in the middle of the conversion, and your sharing has saved me much time and probably $$... Tech support should be your handle...
Things worthwhile usually take longer than anticipated....
5 months later and my 89 YJ is still running sooo much better than the carb / vacuum mess. Worth the time. Your video's accurately showed all the pitfalls of mine as well. Saved me a lot time / potential frustration, thank you! Found out the previous owner like duct tape as soldering, more time in fixing other things than installing the actual TBI. ha
That's great to hear. And, duct tape doesn't actually fix everything!
The kit has worked without a hitch, even as the weather turned colder. Once in a while the RPMs take a few seconds longer than seems necessary to come back to idle when I pull it out of gear (I have a manual) but that's REALLY minor. On your '76 the kit would be even easier to install, except that you might need to weld in the bung for the O2 sensor in your exhaust. Anyway, I have no complaints about the system--it just starts and runs now with no drama.
I bought a 1964 Cutlass with the Howell system on it. You helped me figure out where my fuel filter is, Thank You.
Great video, I was able to find and buy my cj7 back after 21 yrs . It was converted to a Howell Fuel Injection from carb. Lots of different hands have worked on it prior to me getting it back. I’ve put in a lot of time in getting it to work correctly. I’m kicking myself for not finding your video sooner. I did call Howell tech support more than once and basically got the replace part and if does not work then replace another part , basically I tried the new parts and then when problems did not change, I just put old ones back on. Otherwise I would have been looking at hundreds of dollars of changing parts that were fine. I was finally able to resolve my problem with just very methodical patience and tracing the wires to make sure everyone had a proper connection. It was a simple fix, but it was just very hard to find , not having the experience and knowledge with this system. I do electrician work and lots of trouble shooting on complex line and low voltage for a living . Most of the time the problem boils down to connections or wrong wiring which does take time to figure out. Very rarely do I have to replace a major part or small part. I felt that Howell tech support was very impatient and lacked any helpful advice except replace parts then goodbye seemed to be their motto, was wondering if anyone else has experienced similar problems with Howell tech support.
Funny you mention the lack of support--I also found back when I did this that their support was lacking. The directions they send with the kit are written like a 5th grade book report. The information is there, but what a mess! I even offered to re-write the installation sheets professionally, but that fell on deaf ears. Anyway, if you have issues in the future remember that the system is essentially a Chevy truck from the 90s. You can find lots of diagnostic info online by searching for mid 90s six cylinder Chevy pickup trucks.
Thanks for the video. I'm doing my howell install right now. Its a very liberating feeling tearing all the old emissions garbage out.
Yes! It's really amazing how much bulk and weight that stuff takes up. Good riddance.
I've been going over and over through your vid...my engine just showed today.
Thank you so much for the vid. I pulled the old computer out, and messing with the wires now. I cut "ALL" the wires associated with the bundle to the batter tray, and then your vid showed me I needed the relay for the manifold heater. So i'll be re-solidering, thanx for pointing out the two yellow wires, one will go to the heater manifold, the other is going to be power to the HEI ignition.
It is a tricky thing to trace all these wires and remember what you need and don't need. After you're done it actually makes sense, but in the middle of it the task can be daunting!
I bought it directly from Howell on the theory that they would be more eager to provide support if I bought it from them. It was the same price as in the catalogs. But, I ended up figuring it all out for myself anyway.
tinderboxarts talking to them is a waste of their time and they do their best to infer it. Thanks for the tip on being like 90s Chevy truck set up . Also thanks for getting back to me. Keep up the great videos, who knows maybe you will put their lack support line out of business. I just refer people to your channel if they want to learn about this system
@@jasonlenihan9854 I want one of these systems but they DON'T answer questions via email, I looked at their instructions and they seem complicated, the CONCEPT of all GM proven technology and NOT having to do setups & adjustments on a separate screen box I LOVE ! I pay the price they want and can't get Customer service would be not good advertisement
This video was not only informative but he cracked me up! Funny stuff 😀. Thanks
Very nice,I'm doing the same thing...thanks for the information
Its weird that there is duct tape on the factory harness where the wires were spliced together. I had to trim that off and use electrical tape when I did my install. Just didn't seem right to leave it there.
And here I thought it was from the PO.. great to know I'm not the only one who was like wait is this duct tape over a splice??
So power to the fuse block doesn't need to be a constant 12v? From the install guide it's a switched source when in the crank and run position only. Tracing the wires from my harness near the fuse block shows 3 fused wires, 1 goes to the ECM and the other 2 go to the injectors. So how does the ECM keep it's memory?
Also what colors were your check engine light wires?
Hi again.
I just have wiring left. I notice that there were some left oflver wires. Those came from fuse box. Rest where pulled our. Also what air filter assembly did you for assembly on top of f.i
The air cleaner is a tricky factor because if it is too big it will interfere with the brake vacuum booster. I ended up buying an inexpensive ten inch open air filter, which is really just two metal plates sandwiching a 10x3 air filter. Honestly, I thought it would be temporary until I found something better, but it's been on there for years now and I've had no problems.
I admire you making this video and showing how to install this unit. Myself, I would pass this up. The time and effort working on the jeep to update it is not worth it to me, just my thoughts. This is far from a plug and play install, which I know it's not. I would buy another jeep lol.
Well, I installed this fuel injection system ten years ago and the Jeep is still going strong with it. The Jeep has at least doubled in value in that time too. So, yes, there's some effort in getting the EFI installed, but keeping an older vehicle like this on the road often requires some extra effort.
@tinderboxarts just watching you take apart that harness made me quit, lol. There is no way the average jeep owner will succeed in doing this
Anthonie Galvan--I'm not sure a follow your question, but I suspect you may have become confused about the directions for your model year. There are differences in the wires that you describe depending on model year. Go back to the Howell directions (linked in the comments here) and double check that you used the right procedure for your model year.
I would love to see more photos of the vacuum line connections after you installed the TBI. I have an 87 YJ (automatic transmission) that I just competed the conversion on. It runs, but I don't think the vacuum lines are hooked up properly. Any help would be greatly appreciated.
If you pause the video you can see the vacuum arrangement at around the 22:48 mark. Unfortunately, youtube comments don't allow photos.
Sir, thank you for your efforts. Ten years later and I'm installing this system on my newly acquired 1990 YJ. Howell must have sold thousands of these kits. How have the last ten year been in terms of reliability? Anything you would have done differently today?
Has it been ten years?? Wow, time flies when you are having fun! The kit has been pretty much trouble free. I think I did replace the oxygen sensor at one point because it was not performing correctly. Other than that I can't recall any issues.
my dura spark has a black and white braided line going to it from the distributor. It doesn't match the howell schematic for the duraspark. do i cut and rewire following diagram
I don't think I can answer that remotely over the interweb, but all I can say is don't get too hung up on color coding. Sometimes the wiring is just a different color because someone rewired it or it's a different year than in the directions. Take a step back and trace the function of the wires in question. You should be able to match up the function of each wire in the Jeep and match it to the Howell directions, even if the color is different. If memory serves me, I think the ECM just needs a tach signal from the negative side of the coil.
So I just swapped in this kit and I’m having a sputtering issue that I can’t figure out. It runs and starts but I have this air sucking sound from the intake that with go away after it warms up. It revs fine during the warm up but as soon as it’s warm it backfires out the intake. And if it doesn’t and the hard air sucking sound doesn’t go away it sound like a lawnmower popping out the exhaust
Boy, it could be a number of things based on your description. A vacuum leak comes to mind first. Aside from the vacuum hoses, there is the throttle body itself which I think is supposed to have one port capped off if memory serves. And there is the throttle body gasket which could be leaking. And there is the brake booster vacuum line which may have been disturbed or cracked when you were working. You can get a can of carb cleaner or similar and spray it around these areas with the engine running to see if the RPM changes with the spray. It may be that as the engine heats up and materials expand, the vacuum leak seals itself off. Another possibility is a fault with the throttle body, such as an injector not working properly. But the backfiring you mention muddies the water. That can be associated with a spark timing issue. Maybe you mixed up plug wires when putting things back together?
I am about to attempt the same. 90 Wrangler. I am mechanically incline. but the wiring is the scarry part. How did you handle the Pulse air sytem. Cut and cap the end? where did it end? At exhust? Thank you so much for you video, made it easier for me to make the on the challenge!
The pulse air system just gets removed, and if memory serves you can cap off the port into the catalytic converter either by welding it shut or installing a cap over the pipe stub. Or you could replace the whole cat if it is time anyway. The wiring seems daunting, but just take your time and lay it all out with labels before you make the cuts. Once you start labeling everything the number of wires is cut down and what you need to do becomes more apparent.
@@tinderboxarts Thanks for the response. This was a family wrangler from a family member that died from cancer and it was in bad shape. Rusted out cooling system(pump, Raid, thermo and housing). head gasket was blown. So is a project for few more months. Could not get vacuum right and was really a hard cold start. I talked to local guy that only did jeeps. He said he would not work on these carbs anymore to many issues and Stepper motor is no longer available. I will send pics once i am done. again thanks
Juan
That's great you've taken on this project, I'm sure it will be worth it in the end. If it makes you feel better, the switch to throttle body fuel injection is night and day from the old carb. You'll be amazed.
@@tinderboxarts What about the 4 in and 10 in vaccum at the firewall. do we cap those or is it used for something in the inside of the jeep?
Juan. Again thanks for you response and help
You're testing my memory now. The only things I can recall are that the 4x4 engagement of the front differential was controlled by vacuum. That mechanism frequently went bad. Like many others, I installed a mechanical cable in it's place. Possibly a heater flap was vacuum controlled. In any case, it's nothing super critical so you could leave it off for now and if you discover something missing add it back later.
Did you ever find out what the orange and black wires were for? the ones behind the defroster duct. I am half way done with this install on my 87 YJ.
No, I never did! Maybe some things are better left a mystery. The kit has continued to run well on my '90.
I pulled the entire heater out to find out what was back there. And nothing. So I clipped them off.
Hi there buddy I took my 89 to the mechanic to install this kit and he mounted everything good nice clean job but he messed up the Jeep never worked. It starts but if I let go of the key it turns off I need to hold the key on for it to stay on. Now I can find the dam mechanic and I have no idea what it is , plus he removed the white tags that came with the harness any help will be greatly appreciated thanks
Oh boy. So, normally the key is switched to the start position momentarily to engage the starter, then you let go and it stays in the run position. Are you telling me the key won't stay in the run position? I'm just wondering if your real problem is the ignition switch and it was just coincidence that it broke at the same time you had the Howell system installed.
The switch feels exactly like before the efi. Example first click is instrument panel second is crank and normally it has that little spring tension at the end as soon as I let go of that tension it turns off
The issue now is that the mechanic got rid of the old harness so I don’t know why goes to where I think the problem exists in the switch power but not sure since am not a mechanic if I could see what wire goes where I can probably fix it
@@tinderboxarts hey buddy sorry to bug you again but your the only one with this info in RUclips. So I got my Jeep running and now I took it to emissions test but it fail the guy said is missing the line from the charcoal canister to the fuel tank and is true I don’t see a line connected to that port in the canister but what confuses me is that I only see two metal fuel lines under the Jeep one is my filter and pump and the other one am not sure but it’s also plugged into the back of the tbi and I don’t see any other line that could plug into the canister from the tank ? Any help will be appreciated
@@Divinemindset04 I have to laugh because in New Jersey they don't even inspect vehicles older than 1996 anymore! The fact that your local inspection is actually looking for charcoal canister lines is crazy. Anyway, you are testing my memory a little bit. There should be three lines going to the tank, a fuel line supply, a fuel return, and the charcoal canister. If your canister line is missing you may have several choices. Possibly you replaced the entire fuel supply or return lines with braided line when you did the Howell installation. If you did and the old steel tube is still there you could re-purpose it for the canister. If you still need that for the fuel, then you'll have to look at the tank to see where the canister line would have entered. It's been a long time since I dropped a YJ tank, so I can't remember what it looks like. The way these canisters work is that fuel vapors from the gas tank are basically sucked into the charcoal filter for storage and under certain conditions the engine vacuum is sent to the canister. When that engine vacuum is applied to the canister it supposedly clears out the stored vapors. In more modern cars there is a system which monitors the gas tank pressure and throws a check engine light if it senses a loss in pressure. That's why a loose or leaking gas cap can sometimes cause a check engine light. But, in the old YJ that system doesn't exist. So, about the only thing an inspector could do is visually check for a line between the canister and the tank. Unless he uses a smoke machine or a vacuum tester he'd have no way of knowing for sure if the canister is working. Probably all you need to do is get your head under the tank and look for a port that used to have a hose attached. You can run a rubber hose from that tank port all the way to the canister, or you can put a metal line along the frame rail and use a rubber hose on either end for the connections. The charcoal canister was factory, so there must be a port at the tank somewhere.
hi, we spliced in the supplied purple wire to # 18 purple wire from original module and jumpered #47 & 59 together. i assume this is the signal for injector pulse from distributor, but it does not tie into the howell ecm since the original harness is disconnected, so we have no injector pulse. did you run into the same problem? how does the howel ecm pick up the distributor signal when the original harness is now unplugged?
The old YJ had at least 50 points of failure in fuel, spark vac alone.
Hey great vid, it's been 6 years and still very useful!so I'm about to have my 258 rebuilt and once it's done I'll be doing the conversion. My question is the 2 hoses going to the stock air cleaner one being downstream air injection tube port from the cat (gets capped) and the 2nd upstream air injection tube port is coming from the front exhaust pipe right under the connection to the manifold, does that get capped too? Sorry so wordy.. thinking I should be able to get away with just getting a new complete exhaust setup without the 2 ports mentioned above.. thanks for your time and again great vid!
So, the air injection system was an ill-fated design meant to inject oxygen into the exhaust stream and catalytic converter during certain periods. The point was to make the catalytic converter more efficient and to give unburned gases in the exhaust a chance to burn off before exiting. There have been other similar systems which inject air, although not with the confounding valves! With the Howell system you are essentially turning your Jeep fuel system into an early to mid 90s Chevy truck. That entire pulse air system is no longer relevant and you can remove everything. The tube or "port" coming out of the existing catalytic converter can be plugged any way you find convenient and the same goes for the exhaust. When you go to replace that cat when it rusts out or stops doing it's job, you can just insert a universal style without the port and be done with it. A universal cat is actually not that expensive so you may choose to do it from the git-go.
@@tinderboxarts thanks for the input! Wanted to double check before I go ahead and order a new complete exhaust system.. my Jeep has been down for far too long. Did the nutter bypass with the Carter carb that I've had to rebuild a few times.. was going to go with the Weber carb but I'd rather finally have run legit.. thanks again have a great day and stay healthy!! ✌️
I am thinking about a conversion on my 89 YJ. What would be a reasonable labor price for a professional shop to do the install? Tx
You know, most shops are not going to want to tackle something like this at all. They won't want the liability, they are probably unfamiliar with it, and they typically stick to OEM stuff only. You'll have to look for a specialty shop in your area, maybe one that does 4x4 off-road work, or one that builds hotrods or restomods. It wouldn't be cheap. If this is beyond your skillset to do yourself then your better bet is probably to find a friend who works on cars to help.
Hi. Do you happen to remember the sizes for each of the vacuum lines that you connected to the CTO valve?
I'm sorry, I don't recall. I usually just buy a few lengths of each size at the parts store and use them up as I need them.
About to do this conversion on my 90 yj. Was wondering if any special tools are needed or would help in this job. I have done a lot of basic work on it over the years, but this would be the biggest job yet. Would love some pointers to help me along. Love the video
Caleb Smith Standard electrical and automotive tools are all you'll need. One exception may be an electric soldering iron used to "tin" the ends of wires or to solder two wires together. When the installation called for joining new wires to the old harness I soldered the two wires together and covered them with shrink-wrap insulation. There are mechanical connectors you could use instead, but they tend to corrode or come apart over time.
Other than that, just take the time to pull the harness out and apart so that you have everything out in front of you in the engine bay. The first cuts are psychologically difficult, but after that it get's easier! The fuel pump installation may take a little more time then you think, but just take it one step at a time and it will all come together.
Question? What wiring did you use for the supplied fuse box? Will one of the switched yellow wires left from the ecm removal work that is switched power? Also I didn't run the manifold heater relay wire. I never had the green wire coming from my manifold so I just reconnected the wire that it originally had I also went through allthe wires and never saw it being affected by wire removal.. I used your video for guidance thanks, Also my manual said to connect the vacuum from port A off the howell tbi , you used J? Do you think it matters? The other one I capped.
Different year Jeeps can have different options and connections, so yours may vary. It's been too long for me to remember wire colors! Your Jeep could be older and doesn't have the manifold heater.
I'm currently doing this install on my 89 Wrangler and have a question for you. The PO of this jeep had the gas tank vent hose removed from the canister to the tank. The instructions say to hook up your return line from the throttle body to the line previously used to vent gas vapors to the tank. This is where my confusion is. I currently have 2 gas tank lines that I need to hook up and I'm thinking the smaller line on top of the frame rail which is the tank vent line is supposed to go to the canister and the line underneath the supply line hooks directly into the return port of the TBI. I've tried contacting Howell to make sure this is correct but have gotten no response, hoping you can help! Instructions aren't written clearly for someone who's never done the install. Thanks. Your video has helped a lot.
I just went out to look for you. You've got two fuel lines, one for the supply and one for the return. Then there is a small vapor line which is steel along the frame rail, which changes to rubber for a foot or so before it enters the canister. Look at the video and freeze it at 22:56. You'll see two T vacuum fittings. The top one is your answer. It has one line leading from the top of the valve cover to the left side of the T, it has the canister line on the right side of the T, and you can see where it enters the throttle body. I think that should answer your question.
awesome thanks for the reply!
Do you remember which wire you used for the crank and run 12V source for the CPU? Did you use the 'start' (green wire) for that, or did you even end up using that one?
It's been too long for me to remember that, but Howell has the manual here if you need it:www.howellefi.com/pdfs/jeep_kit.pdf
All these years later and I have the same question. Did you ever figure out the crank and run 12v source?
On the ignition module,the fourth wire that you added to the plug we’re does it go? I got lost there, you pink wire , what does that pink wire control?
You connected to a purple wire we’re does purple wire go on the ignition box
I'm sorry--it's been way too long for me to remember, but your Howell packet does explain it somewhere.
By the way, do you have a video of the jeep running and driving with the howell efi? :p
I don't yet! It has continued to run well and it has a nice growl to the intake when you romp on it! When the temp gets below 20 degrees it sometimes runs slightly rough for about 15-30 seconds, but I think that may be a bad intake heater on my Jeep.
Hey tinderboxarts!
I'm back... :)
I've finally converted my cj7 to the gm tbi... But the ecm is flashing the codes: 42 and 43.. Meaning it has no spark control.. --I guess because I DIDN'T install it.. Any suggestions on how to make it go away OR what distributor to get to allow the ecm to control it? I've already tried to connect the b7 to c11 to fool the computer.. But the check engine light still illuminates and runs like a dog... :(
I think code 43 might be the knock sensor. Did you install that? If the CJ7 doesn't have a place to bolt that on you may need to fabricate something. At the very least, connect the wire to the sensor and leave it hanging somewhere. Code 42 I think may relate to the tach signal for the computer. Did you connect or splice the tach wire to the tach signal from the distributor? Even your old CJ will have that, although you'll have to look up which wire it is. Without the tach signal your computer will be in "limp home" mode because it has no idea of engine RPM.
No. I didn't install the knock sensor. Do you know if I also have to install a distributor that will allow the ecm to control the timing?
I installed the tach wire to the "-" side of the coil. :o
rag Doll
No, the ECM just controls fuel. It will work with pretty much any distributor. There is a special note about MSD ignitions, though: "NOTE: Multiple spark discharge ignitions require a special Tach filter to function correctly. Contact Howell Engine Developments if you need one." Of course, the problem could be a bad ground or a voltage drop from a poor wire connection. Take things one step at a time to find the issue. And, you'll have to rig up something for the knock sensor. I think I show in my video where it is supposed to go.
I should have said that I didn't get the Howell kit... Instead, I bought a reman ecm and gm tbi... ")
Therefore the ecm is complaining that it doesn't have spark control. I've read I could have the eprom chip reprogramed so that it only controls the fuel, like Howell kits. But I really would like to have it control spark/timing.
Also, I ran the ground wire from the intake directly to the negative battery terminal, so there shouldn't be any ground issues. AND I installed a separate 12volt wire directly from the harness (with fuse of course) and the ignition coil positive side... So, both of those should be fine.. ;)
Thanks for your suggestions. I've contacted Howell and affordable and neither have responded to my emails. :0 Next, I plan on calling them. :)
+rag Doll Did you get your spark timing sorted out I am doing the same swap you did and thinking of using the gm hei dist so spark timming is left out of the puter
Where can I find a dual cto valve? I have a 89 yj and have the same configuration under the hood, and same Howell conversion kit. I stumbled across this half way through the conversion, my cto valve is toast, and I'm having the hardest time finding one. I can't find one anywhere.
They are right under your nose! Only Jeep calls it a CTO valve--everybody else calls them a ported vacuum switch. You can pick one up from Amazon: www.amazon.com/gp/product/B000C83RF0/ref=oh_details_o08_s00_i00?ie=UTF8&psc=1
I have a 90 Wrangler YJ and I'm installing the CARB Howell kit right now. My thermal air cleaner has a 2 inch duct tube that goes to the exhaust manifold and I'm assuming yours did too. What did you use to cover the outlet hole on the exhaust manifold after the conversion?
Do you mean the hot air duct from the manifold to the air cleaner? That's designed to help during cold-start up by sucking air past the manifold, which heats up quickly. On the manifold is just a little sheet metal receptor for the duct tube. There is no actual hole in the manifold, or if you have one there is a problem! You can just leave the duct tube off if you're using an open air cleaner with the Howell system and the sheet metal on the manifold can stay where it is.
Great vid, I'm swapping my engine in a couple of weeks, slowly getting parts together that are more robust rather than reuse. I put a weber carb on last year. it helped (sort of) but I'm going to do the howell with the new 258. question though.did you swap out any ignition? I did the nutter, but would't start so shifted back. I was thinking of doing a different distributor and coil.
STEPHEN PORTER Yes, I did change the ignition many years earlier. I can't recall the maker of the ignition coil, but it was a more powerful unit based on the Ford TFI. As you probably know, the Ford TFI system from a 1981 Ford F150 truck will swap in (1978-1990 Jeeps), which gives you a more robust cap and rotor, the more powerful coil, and wires to match. It was well worth the minimal investment and has been easy to maintain.
Okay then I had a question I'm ready to turn on the jeep but when I go to crank the jeep over the fuel pump gets no power but when i do click the switch on I do hear it come on for a few seconds but when I go to crank it loses all power
Manuel Hernandez I can't give you too much advice from memory, but it sounds like you may have either crossed a wire or missed a wire. You need power to the pump with the key on, obviously. Go back and sort through all the wires to make sure you didn't miss one or pull power for the pump from the wrong source. Those Howell instructions are badly written but all the information is there if you search through it.
Hey I was wondering in doing the same set up for my 1988 yj but I was wondering do I need to buy a crankshaft sensor for the conversation
Manuel Hernandez The system is essentially the same thing found on mid 1990's Chevy trucks. No crankshaft sensor is used.
Great Video! I picked up a 90 yj and the guy I bought it from did the conversion. It runs rich and I have not been able to figure out why. Any ideas? I thinking it has something to do with how the Vacuum lines were hooked back up (or not). The Howell instructions are not good with diagramming them. Can you tell me how I would know if they are all run correctly?
Coincidentally, I just recently noticed mine seemed to be running a little rich too! I haven't had a chance to investigate yet. Keep in mind this system is basically identical to a 90s vintage Chevy truck. Everything that applies to those fuel systems applies to the Howell Jeep version. So, there are a bunch or sensors that tell the computer how to adjust the fuel/air ration via the throttle body injectors. The O2 sensor is one obvious place to start, since that attempts to measure the exhaust of the engine for oxygen so the computer knows if it is rich or lean. The MAP sensor is another place to look. There is a temperature sensor to tell the computer when the engine is at operating temp, and if that goes bad the computer will stay in a warm up mode that is too rich. Even a faulty throttle position sensor can trick the computer into a poor fuel mix. So, I would first check out all the sensors for proper operation, and there is loads of info on how to do that if you look under 90s chevy trucks with TBI. A complete check only takes 30 minutes if you have a multimeter and the specs at hand. I doubt the vacuum lines are your issue.
tinderboxarts thanks for the reply. I do have a multimeter. Where is a good place to look for the specs? Are they the same for a yj as they are for a truck?
You can download the Howell install directions if you haven't already, and somewhere in there they list the actual components and manufacturer model numbers. But, this is all pretty vanilla Chevy truck stuff, so you can get the info from Chevy sources (I hesitate to post links here since they may disappear later). I mean, the O2 sensor is a single wire model that will vary between 0 an 1 volts in operation. Just look up on the interweb how to test a single wire O2 sensor and the generic instructions will work. Same with the MAP sensor testing--just look up the generic directions. If a buddy or the library has a Chiltons manual for a mid 90s Chevy truck, the component tests shown there will also be valid.
So, just wanted to circle back on this. I contacted Howell after the sensors all checked out OK. They want me to check the fuel pressure (should be between 11-12 psi). Im not sure how this could be causing my issue, but willing to give it a shot. Any idea if too much or too little pressure would cause it to run really rough when first started in cold weather and then be OK with the engine warms?
Wasn't your original problem that it ran rich? The rough cold start issue is a little different. Fuel pressure is basically good or it isn't good, meaning that the system needs enough pressure to do it's designed job and it also needs enough volume. If there isn't enough pressure or volume it usually means the engine will run very poorly or not at all. Yes, it is possible for the pump to be providing marginal pressure or volume and the computer tries to make up as best it can for the issue, but I don't think this scenario is all that common. It can't hurt to test the fuel pressure, but what you are describing now is a rough running engine at cold weather start up and smooth performance when the engine comes up to operating temperature. In the old days when you had a carburetor the choke took care of this problem by providing a richer mix during warmup by constricting air intake. With computer controlled fuel injection, the computer provided the same function by enriching the mix for a period of time or until the temperature sensor tells the computer the engine is warmed up. So, again, the computer relies on the sensors and the wiring to the sensors to be accurate in it's programs. Now, if you are running rough only during the period when the engine is cold, it seems likely that the mix is leaner than it should be. Assuming that the fuel pump is providing enough gas and assuming the sensors AND the wiring to the sensors is good, then a vacuum leak could be another culprit. There are two old school tricks for testing this. One is to use a can of carb cleaner and spray it heavily around each of the vacuum hose connections while the engine is running. If there is a leak, the RPM will dip when you spray heavily by the leak. Don't forget to spray around the base of the throttle body, where the gasket itself can cause a vacuum leak. The other trick is to use a pair of needle nose pliers to squeeze off each of the vacuum hoses to see if the RPMs change. Since testing for a vacuum leak is quick and easy, you may choose to do this first before moving on to more esoteric issues.
Hello, May I ask you for an update? How has it ran for you since then? Do you have to smog your vehicle in your state? I am just about ready to go get inspected......scouring the internet for info on what to do with the pulse tube....I see you capped it off, but I might need it for smog.....it is used to get the cat hot enough to start working....
Anyway, I just wanted to say thank you for sharing you video. I seen it several times years ago before buying my kit, and
now came back again for reference.....good video ;)
It's still working well. I did just replace the o2 sensor, which was defective. The one supplied is not very good quality. Other than that I've had to do nothing. It did pass my NJ inspection previously, but now NJ has changed the law and anything older than 1996 is exempt anyway. If you're worried about the cat, you can source a different universal style which will not have the tube.
So I'm also doing this on a 90 yj. How long did it take. I live in California what else was needed to be done to pass smog? A new cat? Any info regarding smog would be much appreciated.
I have zero knowledge of CA inspection requirements. Here in Jersey they don't even inspect cars older than 1996 anymore! However, Howell does sell a CA specific kit, I believe, and they do provide a new sticker for the Jeep to indicate the upgrade. It shouldn't be a problem and I would suspect you'll be fine. The catalytic converter wouldn't need upgrading unless you coincidentally have an older one that has failed. As far as timeframe, that really depends on your knowledge, confidence and tools, as well as the condition of your Jeep. You may end up fixing other things along the way if your Jeep is in ragged shape. If you are reasonably knowledgeable you'll get most or all of it done in a weekend, but it may take longer to deal with rusty bolts or things breaking off in your hands--the usual!
Awesome vid, thank you. I'm mid install and this video has been the most helpful thing so far.
Quick question. The two pin connector on your duraspark ignition, does it plug into a plug with green and yellow wires? Mine have red and white going from ignition to plug, but I can't remember what plug went back in. (I took a *long* break during this install)
I already had an aftermarket ignition, but I can take a look to see what's left...
I was able to figure out my issue. Thank you! I'm just having an issue with the ignition coil now (passenger side). The white tach wire is supposed to go in the same spot as a green/white already there. I'll probably just splice.
Thank you for making this video! I'm in the middle of the instal and making a royal mess with the wiring After. watching you struggle with the wiring harness off the computer, I just quit and left it! I did cut the wires off the diagnostic port by the battery and was trying to walk them back. I hope and pray I didn't cut anything I need in the future, cause I didn't mark a thing. (I know, rookie move but I was feeling brave and stupid) Did you ever go back and clean up the harness? Are you still a fan of this upgrade after all this time. - I still have to find a way to plug the pulse air connections of the exhaust manifold and CAT. I'm telling you I made a mess hahah, but almost done!
Yes, I'm still glad I made the effort and it has worked well for me. I did clean up the harness and put everything back together neatly. Just take your time and take it step by step.
What I did, cut and bend then put a small amount of JB Weld on where you made cut & bend ...no leak
Thank you for posting this!! Do you still own this jeep?
***** Yes, I still have the same Jeep and the Howell system is still going strong. I've got plenty of OTHER issues, of course! ;)This winter it got very cold in my area, but the Jeep started every time. The "choke" for the Howell system seems to take 30 seconds to set the RPM correctly, but it never stalls or fails to start even down to zero degrees. It was definitely worth the effort to install.
Nice Video. It'll definitely help with my install that I'm planning this summer. Right now I've swapped mine to a Motorcraft 2150 Carb. It runs really well but I live In Cali and the smog dogs are upon me so the swap makes sense. Now my questions. Did you see any increase in mileage? How about power? Sure would be nice to see and hear it run... Thanks for the Vid...
At first my mileage seemed the same (about 15 MPG) but my last tank was 20MPG. It might have something to do with the gas formulation here in the winter. I passed NJ emissions without problem. The power is not dramatically different, I guess, but it feels more consistent throughout the entire RPM range. With the original carb it would hit a flat spot around 2200 RPM. Now it pulls steady right through to the higher RPM ranges. My only complaint is that in single digit ambient temps it takes 30 seconds for the computer to really kick in the "choke" function. It still starts and runs fine in those temps, though.
please please help me. this morning it started for a few seconds then it stalled. doesnt want to turn on anymore it just cranks and cranks as if it had a kill switch or something(it doesnt). injectors dropped a few drops but not a spray like it used to. just a drop here and there. the distributor works i know cause i got a nice shock all over my body.lol it was pretty refreshing but i wasnt ready for it. i didnt do the conversion. i just bought it and it didnt do that after 2 days of test drive
You need to go through all the systems methodically. Does it have spark at the spark plugs? Does it have fuel pressure and volume? Is there compression? Do you have a problem with a sensor like the crank position sensor? You must eliminate each system as the cause one by one or else you're just chasing your tail.
tinderboxarts ... i figured it out now sir thank you. it was my fuel pump not delyvering gas all the way to top. thanks for the response
You posted 2013 HOW is it functioning now? ANY issues? I'm considering this setup for my 302 AOD 1965 F100, the ONLY thing keeping me from it is what appears to be unclear instructions
It continues to run strong, although I'm just starting to notice a little stumble that I suspect is the EGR valve. It's all common stuff available off the shelf, though, so no worries. I've been very happy with the setup.
@@tinderboxarts Thank you for your response, now considering the kit for a current FI 94 F150 300 inline 6 , want to get rid of the crap Ford system, is yours STILL running good? Did you ever have to actually talk to them for help??? Your experience with that issue??
@@REVNUMANEWBERN Still running! I think I replaced the oxygen sensor last year, no big deal. I've never contacted Howell so I can't say how their support is, but these are all off-the-shelf components that you can buy in parts stores.
Hi again,
Thanks for your review and upate.
I updated my intake manifold with an 1985 intake and a new exhaust manifold that already has the O2 sensor port.
Does Howell offer a Throttle Body with a kickdown/passing gear bracket? (I have a TH400 auto trany behind my 258.
Am I correct to say rhe ECM is pre-programed and is NOT a ;earning computer?
Did you have to do any throttle body adustments or is it plug and play?
Also, I don't have a computer/brain in my cj7.. Hopefully it will be easy.
Thanks :)
Interesting question on the kickdown for the auto trans. It doesn't come with one but I'm sure you could rig up the existing linkage pretty easily. The computer and TBI are plug and play--get the wiring and sensors right, and they'll just work!
Did it imprive your miles per gallon?
Not really. I think the MPG is going to be about the same. The benefits are more about easier starting, less maintenance, and fewer moving parts.
What’s the stock timing with this kit I have to same yj
The Howell system does not control spark timing, so you retain your stock settings for that.
@@tinderboxarts ok got it
So what is the stock timing supposed to be because mine was at 16 degrees and it smelled like it was running rich
I just looked it up--my books says 9 degrees BTDC normally, or 16 degrees BTDC for high altitude. Maybe you live in a mountainous area?
How did you wire up the ignition coil?
That was a long time ago I did this, but I could take a look for you. Is there a specific problem you are facing?
@@tinderboxarts when the key is on the wire going to the coil gets hot and starts to smoke a little
Boy, that isn't right! Have you checked the coil itself? That indicates an excessive draw.
@@tinderboxarts obviously it’s not right that’s why I’m asking
So, check the coil. Put an ohmmeter on the primary and secondary windings and look for a short. A primary winding has a resistance typically in the area of .5 to as much as 2-3 ohms. The secondary could be in the neighborhood of 5000-20,000 ohms. Zero resistance is an internal short and a very high resistance is an open winding. Different designs will have different specs. On my Jeep I replaced the coil with an aftermarket version, which you may have too.
Where did you buy the kit?
Are you still happy with the Howell? Did your milage move up to 19-20?
+G. oAway Sorry for the late reply, I missed your comment. My mileage is not in that range and I suspect that kind of range is unlikely for anyone except under the most ideal circumstances. 16-17 MPG is probably more realistic and if you are doing spirited driving (who, me?) then 14-15 MPG. I am still happy with the system, though. It has continued to be reliable under all conditions and it never fails to start on the first try. I'll be adding a minor lift and larger tires shortly and I'll be curious to see how the Howell system handles the different final drive ratio created by the larger tires.
tinderboxarts Thanks. I am looking at making the change. I am looking for dependability or mileage. :)
Does not the temperature gauge work?
The temp gauge on the dash and the temperature sensor for the computer are two different things if I remember correctly. Maybe you accidentally dislodged the wire for the gauge (I think it's on the top toward the back of the engine) when you were working?
Or that I could have connected badly so that it does not serve the temperature gauge and jeep
Salut, bien cette vidéo mais il aurait été sage dans ton explication de montage d'expliquer un peut plus les branchements électriques, a savoir quoi va ou !!!
HELP WRANGLER YJ 1991 YEARS ENGINE 4.0 PCM 56026982 NEED NUMBER PART FOR NEW PCM THANKS FROM BOSNIA
Ill pay you to do mine
Ha! You can probably find somebody locally to install this for you, but I imagine it would expensive.