1997 GM Truck Cranks No Start, No Codes
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- Опубликовано: 6 окт 2024
- This 1997 Vortec 5.7 was towed in for a cranks no start condition. Testing leads to a failed ignition coil, leaking to ground under a load. Replaced coil, distributor cap and rotor as well as a set of plugs. Starts and seems to run fine at first then the forward O2 sensors are acting strange. I ended up putting a used PCM in the truck and programming it as required. Still has other issues.
Fixed our 5.7 crank no start with new cap and rotor even though no visible signs of arcing out was clearly extremely old by the corrision built up underneath and on the rotor. Thanks for the video always nice to see someone else's go through before jumping under the hood as im not a daily mechanic so most of what i learn is lost over time. But since learning that subs and thumbs is what helps those of you posting your knowledge on here for us to save big money at shop its the least i can do! Cheers
Phillip, my 97 suburban k1500 work horse starts well everymorning . No hesitate. After a pitstop at gas station ,lumberyard and so on it hesitates say up to 3-5seconds to start. Thanks for the knowledge.
Coolant temp (EFI) sensor may be the issue .
Inexpensive part
Phillip, thanks for the AWESOME video/information really learning a lot from you so what made to go and change the module /programing and i wonder with knowledge you have and sharing it you deserve much more sub in my opinion and been trying to share ur videos with others as much i can CHEEEEEEEERS
The bias voltage on these older GM O2 sensors should be around 450mV KOEO and on this system because the heater circuits simply are turned on with the ignition and therefore should start to move towards 100mV with the ignition on not running. Turned out both rear sensors are dead anyways. Thanks for your support.
I've have changed everything possible I know of you have saved the day
What was your problem. Glad it helped you.
Had 1 that was out 17 degrees cause was dealer installed dist with a spun dampener found true tdc and installed correctly ran great .
Phillip, AWESOME and great information so u changed the PCM because it did not control the O2 sensors or for some other reason and by the way you deserve more SUB for the info/knowledge you sharing and been trying sharing ur videos with others. cheeeeers
I was watching video I never thought of the coil it fiers when let go of key.trys to crank up but thanks allot.
Clean all the ground connections computer will not function properly after a portion of the ground signal is lost
Thank you for posting I can ask what program or scan you use and I like the layout
I'm using a Snap-on Verus Edge tablet
Did you pull the distributor and check the distributor drive gear? Numerous cases of the drive gear teeth being "knife edged" causing the P0300 random misfire code. Something to check.
No I didn't as I know the distributor was replaced and once running the cam sensor offset was at 0 degrees but you are correct the distributor gears wear out and throw out the sync between the rotor and tower causing an abnormally large air gap and weak secondary output leading to random misfire.
Very good information thanks for share your knowledge
Doesnt ignition control module send information to the pcm letting it know when its ready for fuel and spark? Sometimes you can pour a shot glass of fuel on the air filter and they will take right off on a crank but no start issue. I see yours is different though.
No the ignition control module that was under the distributor cap of the throttle body systems did but this ignition module is a transistor controlling the ignition coil.
Nooooo it’s right beside the ignition coil that’s the problem
Hey man i got a quick question for you i got a 99 Chevy c2500 5.7 it had a p1345 code for camshaft/crankshaft correlation so i reaplced the cam sensor now it wont fire up at all ran before just not right
That code is not a failed sensor and to be honest a failed cam sensor won't cause a no start condition. If you removed the distributor then you likely have it out of time. Pull number one plug, turn the engine until you feel compression building in the plug hole then line up the timing mark to the top dead center pointer. Remove the distributor cap and check that the rotor is lined up to the appropriate tower. Also make sure the plug wires are on the correct locations. That code is typically caused by a worn distributor drive gear..
My blazer is doing the same thing, got spark, coil and distributor,rotor and capn,even fuel pump all new and replaced, no start, it's Gita be the ignition control module? Right? I'm not really getting fuel pressure, does the icm have anything to do with it?
Try changing your engine coolant temperature sensor that was the problem in my 98 s10
Thank you so much I can quit pulling my hair out
My 97 gmc 2500 sierra 5.7 was doing this after i changed the radiator. I changed the fuel pump and it seemed to fix the problem only after a few cranks later its doing it again? any suggestions?
Check your frame ground. There is a heavy ground on the lower right side of the firewall between the body, frame and engine. Since the fuel pump is grounded to the frame a poor frame ground will affect it.
What if your not getting spark out of the coil at all? I have a 99 7.4 vtek thats getting fuel, power and pulse signal to a new coil but still not fireing the coil.
Check for ignition power and ground at the coil. The pulse is a 5volt signal from the pcm. If you have those then the coil is bad.
Hey Philip, so I have a 03 Chevy s10 that just died on me while taking a turn off the highway. Tried to start back up but cranked no start. I had this same problem two weeks ago and it took me awhile to figure it out but I ended up replacing the rotor and distributor cap. Fired right up and ran great for two weeks. Zero codes. Then this happened. It’s getting gas and has no spark again. But this time it wasn’t throwing spark from the coil. Any suggestions?
@@PhillipBailey it’s a 6 cyl 4x4 4.3l. It also has a new coil. I’m about to check the terminals now on it. Appreciate your fast response
@@PhillipBailey also just hooked up a test light to negative and put it into the coil to double check the coil. I wasn’t visually seeing a spark connect from the light to the coil but the light would flash if I had it all the way in and was cranking over at the same time but couldn’t see the spark
@goodtripsonly according to my info a 2003 S10 with a 2.2 4 cylinder uses waste spark and does not have a distributor.
@@PhillipBailey it’s not a 4 cylinder. It’s a 6 cylinder 4.3l
@goodtripsonly ok then. The sensor in the distributor is the cam position sensor and it will not cause a no start. Here's what I would recommend to try...
1. Turn ignition on and listen for the fuel pump to run for about 1 second. The MIL must also come on in the dash and Stat on. If neither work check the fuses that power the PCM. If they are good then you will need to confirm the powers and grounds to the PCM. Ok go to 2...
2. You said you have no spark at the coil wire. Connect a test light to ground and backpin the white wire at the coil with the ignition on the light should light bright. If not backpin the pink wire key on. If it lights then replace the coil. If the test light turns on on the white/black wire have someone crank the engine over. The test light must blink indicating that the primary side of the coil is being switched on and off through the ignition control module. If it blinks and you have no spark from the coil replace it. If on steady 3...
3. If a scanner is available access engine data and watch for an RPM signal cranking and injector pulse width. No RPM and injector pulse it's likely a failed crank sensor or wiring. RPM and injector pulse 4...
4 at the ICM by the coil a graphing volt meter to the control wire backpinning the white wire. Cranking you should get a 5 volt pulse to trigger the ICM. If you have a pulse then you have a failed ICM. No pulse you have a failed PCM or wiring to it.
There are a few other things that could be checked such as does the fuel pump run during cranking, do you have injector pulse. Other things like no fuel pressure will cause a no start but won't cause no spark.
May I ask what may cause a no start "only when hot" on 1996 chevy suburban k1500? In the winter time the problem dissapears. In summer it won't fire up until it gets cold the next morning. New distributer,plugs,wires,coolent temp sensor,pvc valve. Fuel pressure at 55 "and holds good" and no codes. Thank you sir!
When it won't start I gather it's cranking ok. You need to figure out at that time what is missing ie spark, injector pulse or both. If you have no spark and no injection pulse could be a failed crank sensor. If you are missing just spark it could be a failed ignition module. Is there an RPM signal on the scanner? If you have both spark and injector pulse check fuel pressure.
Try changing your engine coolant temperature sensor that was the problem in my 98 s10
What was the problem
Hey Phillip I have a 1997 4.3 1500 that randomly shut off on the freeway (ran perfect before that). I can hear the fuel pump going but have no spark now. Could a coil just fail instantly? Not sure where to go…
Also, engine cranks but no codes..
Yes a coil can fail with no warning. Do you have spark at the coil wire? If so check cap and rotor. If not listen for the fuel pump to prime when tlyou turn on the ignition. Bump the starter with the key and listen for tge pump to rerun. If it does this indicates the crank sensor is sending a reference to the pcm. Does the data indicate rpm while cranking? If so you may have a failed ignition module. You need a graphing meter to check for the 5volt pulse to the ignition module. Good luck.
Ignition control modules are notorious for failing and causing internment no starts when hot, although I had one fail when the engine was cold!
The ICM was located under the distributor cap untill 92 / 93.
The thermal paste on the heat sink dries up & the solid state epoxy encased electronics develop internment problems.
My truck doing the same I’m lost I don’t know what to do
It's a process of elimination, scan for codes, review data for failed in range sensors, check fuel pump operation, fuel pressure, spark at plug, spark at coil, injector pulse and fuel delivery. Could also be a mechanical engine problem like jumped timing chain, stripped distributor gear or contaminated fuel.
So I’m dealing with common issues does anyone know where that purple wire is tied into from the coil pack I have a similar wire but the other end is broken off and I can’t find where it goes
I see three wires to the coil none is purple and 4 wires to the module again none is purple. What year and engine? What's the problem with the engine. Sometimes an aftermarket car starter is tied into the white wire as that's a tach signal. Does it have an aftermarket car starter?
@@PhillipBailey at 9:32 you can see the purple wire going to drivers side from the ignition coil harness
@theoholcomb50 as I said that's the tach signal wire for an aftermarket car starter on this truck
2000 4.3 vortex v6 cranks won’t start, no spark at the coil so I swapped it. Still no spark at the ignition coil… should I be checking the distributor cap and rotor?
If you have no spark from the coil it's not the distributor cap or rotor. Does the check engine light turn on with the ignition switch? Does the fuel pump prime? Does the PCM communicate with a scan tool? Codes? Does the PCM read an RPM signal while cranking?
@@PhillipBailey the fuel pump does prime.
One code only, p0442 (small evap leak)
I haven’t checked rpm on a scan tool but I don’t see the tacometer move when cranking
Yes check engine light comes on p0442
@saulguel5404 the gages may be frozen during cranking. Have to watch rpm in scan data. I'm sure the p0442 is unrelated.
@@PhillipBailey should I replace the ignition control module,
No oil pressure when cranking
It will take a bit of cranking to build oil pressure especially if you have not started it for several hours. You did mean oil pressure not fuel pressure?
My 99 round body 5.3 does a crank no start randomly any idea what it could be? One it start it runs good no check engine light nothing just does that randomly
You need to check it when the problem is present. does the fuel pump run on key on for the prime cycle? does the MIL turn on with the key? check fuel pressure, spark and injector pulse...what do you have to do to get it to start?
@@PhillipBailey I do have spark and my fuel pressure was at a 48 the other day when I checked
@@PhillipBailey also I thank I found a ground wire that comes from the bottom of the back driver side of the engine right by the headers that is striped that is not connected to anything
@302chris9 needs minimum 55psi fuel pressure. Sounds like a failed fuel pump. Try spraying some carb cleaner in tge throttle body see if it will run. Could also be a bad fuel pressure regulator but you said you replaced that already.
@@302chris9 that could be the frame ground and may affect the operation of the fuel pump.
My truck doing same thing.
There are lots of causes for a crank no start condition
Hallo
Would this truck randomly start/no start?
It was towed in as a crank no start but the coil could cause an intermittent no start or stall condition for sure.
@@PhillipBailey thanks for the reply, been chasing the same issue for what seems to be an eternity. Crank sensor shimmed, new plugs, wires, cap, icm, cam sensor, coil getting power, random no spark. Coil has been changed, but i think its the next to try.