Awesome video thank you. So just to get what I learned from you clear, you have the old PCM and the new pcm. The old pcm is basically connected to high pressure switch and clutch. Then you get the fast idle wire wired in series going to the new pcm to let the new engine compensate for clutch on. If this is correct then I got that mystery solved. I think the only remaining mystery is cruise control lol
Thanks for that info. Im goin to try this on my box chevy. Mine would idle down also when i turn on the ac but i catch it and give it some gas. Funny thing is that it doesnt do it all the time. My tuner tried bumping my idle up some and it did help a little.
I have the old 5.3 drive by wire harnesses and it looks like trash….😂😂😂😂I can’t do it bruh it’s a headache. Plus the HP tune and pcm is another headache… big ups to you my dude
Maaaan I swear I’m so glad you upload videos of the box lol. I got my LS running in my 79 and now i wanna add A/C and I figured this was the easiest way to do it and you confirmed it with this video thank you 🙏🏻. What A/C hoses and condenser did you run did they come from a 90s caprice also?
@@MrGriffin23 rite on! that’s exactly what I was thinking. You don’t even know rn how much I appreciate this video these hot summer night kill me and my wife 🤣 the wife and I will be very happy to have AC in the chev 🫱🏼🫲🏽
Honestly man, any auto parts store, summit racing jegs a lot of places sell AC compressors so you just gotta make sure you find the right bracket for your set up.
@@MrGriffin23 I have a little more work to do LOL some P59 PCM's won't accept the 12v signal. So, I'll need to desolder a resistor and add 2 to the PCM and it still may need a pressure sensor. Chevy has so many variations of things ... makes these projects fun.
Great vid but what happens if u have a blue green pcm connectors. I looked on the green plug on lt swaps n it says not used but 18 is clutch switch .. is that the one I want cause it’s a green wire??
I have a Gbody Monte Carlo, under the hood it looks almost identical to your car as many GM’s are mechanically similar. Your car is super clean, nice engine swap. So hiding all the stock wiring…is your original engine computer and it’s entire harness still in there too? I took mine out with my LS swap and have no plug to attach to the ac compressor clutch. Do you have any wiring diagrams showing your high pressure switch and AC clutch plug and how it connects to that wire loop tucked under the receiver/drier?
Thank you for watching! My car never had a computer prior. I have a video on how I wired in the ac switch and the high pressure switch. I’ll have to find it. It’s pretty simple tho as it’s all tan in series together.
❤💪 thank you much needed explanation on it. Can you show or get a stock wire schematic of the high pressure switch? Where to get the wires from. My 84 doesn't have a high pressure swith, just the clutch plug.
RUclips sent this into my feed, and I'm so pleased, I thought the car looked familiar, I remembered the CC article! Are you running SpinTech on your Impala? Where's the Turbo T? I have a few 69 Buicks, including a California GS, I have a '69 4D HT I want to LS swap, and I might already have a 6.0 for it...Tacoma, right? I'm up in Snohomish (Clearview). Stay safe, you and your fam through these trying times...
Hey! Good to see another from the area! I’m running Hooker Aerospace Mufflers on my Caprice. Spintechs 9000 on my Chevelle. The Turbo T is down at the moment. But tomorrow, I’m going to diagnose it. I love those year Buick’s. I had a 71 Skylark Convertible. Loved that car. LS Swaps are fun. Pretty straight forward. Good power! You stay safe as well!
Your blend door inside heater box might not be sealing. It’s pretty common on old GM cars. They used a foam padding on the blend door on some makes and models and that usually deteriorates after time. The blend door blocks/directs air. If it doesn’t seal air is allowed to flow freely. That would be worse case. You can also check behind the dash. Sometimes the vacuum lines come unplug from the selector switches or random lines can sometimes be bad, but I think them failing isn’t too common but can happen.
@@MrGriffin23 I have the same problem I'm only getting air thru the floor I think it's the vacuum lines where do you tie those in if my car been ls swapped
It’s from a early to mid 90’s GM truck, SUV or S10. I wouldn’t recommend. Too much work to make it fit. I would just get the ICT Billet or Dirty Dingo. $200 and be done. I spent way more time trying to make this work than I wanted
ruclips.net/video/zVqClRhrMyg/видео.html Fast Fwd to 4:20. I explain it there in reference to my particular R4 Compressor. Not sure if it will work with yours unless you are running the same.
Excuse me, which is the sensor that controls the compressor off cycles, I did the swap, install the low-pressure sensor for the accumulator, install a relay and it turns on well, but the detail is that the compressor does not turn off.
The low pressure switch allows it the cycle. If you are running the R4, you need the high pressure switch and it has to be ran in series with the low pressure switch and tied into the power wire that turns on the compressor. ruclips.net/video/zVqClRhrMyg/видео.html Go to 4:00
@@MrGriffin23 Could you give me your number to send you a photo of a diagram that I have to see if it works for me I have been trying to fix that problem for a long time and I can not
Hey man is it possible you could email me a schematic of how you wired your fans to come on with the ac, but still be controlled by the PCM, it has my brain scrambled and it’s driving me nuts lol
I don’t have one written out. I just followed some diagrams I found on RUclips. Here is a good video. ruclips.net/video/Ckerl1Bk2jo/видео.html Hope that helps some. I can locate a few others too if you need. Sorry if I’m not much help. I’m in the middle of moving and not driving the car much
Just joking, I'm having issues with my swap and we are watching videos all the time to see how people is handling the a/c compressor relocation and the speedometer.
Ruben Salais Gotcha! Yeah, I did it a budget way by using an old 90s style AC bracket. I wanted to dave money but a sure didn’t save any time. It was more work than I anticipated. I’d just used the ICT Billet bracket. Speedometer, I just use my tablet and an OBD2 transmitter. Sometime down the road I’m going to get the Dakota Digital conversion box to have my regular speedo cluster work.
@@claytonhaske Too detailed to comment on, but you have to wire the high & low pressure switch in series. Also the power to the compressor needs to come from the climate control selector switch and it should have another lead going to a relay. At least that’s how my R4 compressor is wired up.
@MrGriffin23 since the high and low pressure switches are in series. Do you have the relay before the pressure switches or after them, between the pressure switches and the compressor?
@MrGriffin23 so, it goes a/c switch(dash) to factory low pressure switch, the to the compressor high pressure switch(wired in series), then the relay, then the compressor?
I just put a 5.3 on my 94 Chevy truck and I was thinking on doing the same thing, using the ac bracket of the 4.3 but I guess I’ll just go ahead and order one on line
@@alvaroibarra469 It definitely won’t work if you are not running a Procharger. That belt was running that unit as well as all my other accessories. It will be too long. You should measure it to be sure with a ribbon or a piece or thin rope
Stateofsteezo The wires that go to the compressor should have a two prong plug. They typically had 2 dark green wires to one side of the plug and 2 black wires to the other side of plug.
How is the high-pressure sensor installed in the ac line? I already have my electrical connection from the ecm, only I don't know how the sensor is installed, welded or seva a special adapter, I am leaving the original compressor and the hoses
Francisco Muros I will look it tomorrow to confirm. If I can remember correctly, it’s hooked up in series with the low pressure switch. As far as you running your original compressor, I’m not sure if it’s the same.
Awesome video thank you. So just to get what I learned from you clear, you have the old PCM and the new pcm. The old pcm is basically connected to high pressure switch and clutch. Then you get the fast idle wire wired in series going to the new pcm to let the new engine compensate for clutch on. If this is correct then I got that mystery solved. I think the only remaining mystery is cruise control lol
My car didn’t have a computer prior to the LS swap. Other than that it sounds like you got it.
MrG. This was a very thorough diagnostic evaluation of the situation. 😄😄😄✌🏾💯
youngestson 65 Just trying to help another out!
Thank you Mr.G. for your valuable information. I just subscribed to your channel. Good content. Keep up the videos..👍
Appreciate it! Glad it helped. Stay tuned...
Thanks for that info. Im goin to try this on my box chevy. Mine would idle down also when i turn on the ac but i catch it and give it some gas. Funny thing is that it doesnt do it all the time. My tuner tried bumping my idle up some and it did help a little.
Keep me posted how it works for you! Thanks for watching?
just was looking for this info some body was like mr griffin did it lol i was on my lil hiatus when you originally dropped it
LOL! Fa Sho!
I have the old 5.3 drive by wire harnesses and it looks like trash….😂😂😂😂I can’t do it bruh it’s a headache. Plus the HP tune and pcm is another headache… big ups to you my dude
Appreciate ya! Thank u! If definitely a grind!
Great info Mr. Griffin 👏🏾👍🏾👊🏾
Glad it helped!
Maaaan I swear I’m so glad you upload videos of the box lol. I got my LS running in my 79 and now i wanna add A/C and I figured this was the easiest way to do it and you confirmed it with this video thank you 🙏🏻. What A/C hoses and condenser did you run did they come from a 90s caprice also?
Yep! Entire set up from a 89-90 Box
@@MrGriffin23 rite on! that’s exactly what I was thinking. You don’t even know rn how much I appreciate this video these hot summer night kill me and my wife 🤣 the wife and I will be very happy to have AC in the chev 🫱🏼🫲🏽
@@NORTH_HWD All good brotha! Glad to help!
Loved video can u tell me where I can order air-conditioning set up for my 1978 ls swap impala
Honestly man, any auto parts store, summit racing jegs a lot of places sell AC compressors so you just gotta make sure you find the right bracket for your set up.
Thanks bro I been trying to figure this out for a while lol👌🙋♂️💯
All good! Glad it helped
Great video we learn something from each other every day let’s keep it in rotation
RichEverythang Greed!
What PCM are you using? Thanks for posting this.
Gen 3 from a 2002 Tahoe. No problem. Glad it helped.
@@MrGriffin23 Yes sir. I’ve got an ‘86 C20 with an ‘06 lq4 that I’m trying to get cleaned up. Huge help running across your video. LIKED AND SUBBED!
@@DizzKidz Sounds like a great project. Awesome! Glad the video helped. Appreciate the support!
@@MrGriffin23 I have a little more work to do LOL some P59 PCM's won't accept the 12v signal. So, I'll need to desolder a resistor and add 2 to the PCM and it still may need a pressure sensor. Chevy has so many variations of things ... makes these projects fun.
Great job bro💪🏾💪🏾so the input reference voltage to the pcm is 12volts or 5volts?
D.I.Y With The Richardsons Per my tuner, it’s 12 volts.
Awesome job 👍🏼
Thank u!
Great vid but what happens if u have a blue green pcm connectors. I looked on the green plug on lt swaps n it says not used but 18 is clutch switch .. is that the one I want cause it’s a green wire??
To my knowledge, I have heard with the “newer” PCMs it doesn’t work. I didn’t know this at the time.
Dang good video...Thanks for the info
Glad it helped! Appreciate it’s the feedback!
Good video.. keep it coming ✊✊✊
Good! Glad it helps!
Nice. Great video
Thank u! Glad it helped.
I have a Gbody Monte Carlo, under the hood it looks almost identical to your car as many GM’s are mechanically similar. Your car is super clean, nice engine swap. So hiding all the stock wiring…is your original engine computer and it’s entire harness still in there too? I took mine out with my LS swap and have no plug to attach to the ac compressor clutch. Do you have any wiring diagrams showing your high pressure switch and AC clutch plug and how it connects to that wire loop tucked under the receiver/drier?
Thank you for watching! My car never had a computer prior. I have a video on how I wired in the ac switch and the high pressure switch. I’ll have to find it. It’s pretty simple tho as it’s all tan in series together.
I have a LS 5.3 in a 1986 Chevy caprice which compressor will be good to use?
Sanden or R4 depending on your bracket set-up
❤💪 thank you much needed explanation on it. Can you show or get a stock wire schematic of the high pressure switch? Where to get the wires from. My 84 doesn't have a high pressure swith, just the clutch plug.
Datdude Dewalt All Good! Glad it help! I’ll see what I can do.
Thx
Good info but how did you wire the high pressure switch on the compressor
Check I previous install video as I explain that as well.
Thank you!
Thanks, nice car!
Thanks!
RUclips sent this into my feed, and I'm so pleased, I thought the car looked familiar, I remembered the CC article! Are you running SpinTech on your Impala? Where's the Turbo T? I have a few 69 Buicks, including a California GS, I have a '69 4D HT I want to LS swap, and I might already have a 6.0 for it...Tacoma, right? I'm up in Snohomish (Clearview). Stay safe, you and your fam through these trying times...
Hey! Good to see another from the area! I’m running Hooker Aerospace Mufflers on my Caprice. Spintechs 9000 on my Chevelle. The Turbo T is down at the moment. But tomorrow, I’m going to diagnose it. I love those year Buick’s. I had a 71 Skylark Convertible. Loved that car. LS Swaps are fun. Pretty straight forward. Good power!
You stay safe as well!
Good info good video 👍
Fa sho! Glad to help!
Hey MrGriffin23, would this be the same for an 89 C1500 chevy truck? I only have a low pressure switch at the dryer.
It should. Mine is at the dryer too.
Love the video... my a/c vent at the top is not blowing, but the vents at the bottom are working. Question what u think I should do?
Your blend door inside heater box might not be sealing. It’s pretty common on old GM cars. They used a foam padding on the blend door on some makes and models and that usually deteriorates after time. The blend door blocks/directs air. If it doesn’t seal air is allowed to flow freely. That would be worse case.
You can also check behind the dash. Sometimes the vacuum lines come unplug from the selector switches or random lines can sometimes be bad, but I think them failing isn’t too common but can happen.
@@MrGriffin23 thank u sir
@@MrGriffin23 I have the same problem I'm only getting air thru the floor I think it's the vacuum lines where do you tie those in if my car been ls swapped
What liquid line did you use
89-90 Box Chevy
@@MrGriffin23 thanks. I need that same line for my g body.
Do you remember how the pressure switch is wired on back of the compressor?
Not off the top of my head, but I think I have it explained in a video.
If you remember I could use the help I appreciate you responding 💪🏾
Do you have a high pressure switch on system
Yes!
Which a/c bracket you have?
It’s from a early to mid 90’s GM truck, SUV or S10. I wouldn’t recommend. Too much work to make it fit. I would just get the ICT Billet or Dirty Dingo. $200 and be done. I spent way more time trying to make this work than I wanted
How did you wire your A/C pump? I have a dark green going the a/c clutch and on the new style they have a high pressure switch, how does that tie in?
ruclips.net/video/zVqClRhrMyg/видео.html
Fast Fwd to 4:20. I explain it there in reference to my particular R4 Compressor. Not sure if it will work with yours unless you are running the same.
My swap started cutting off after I did this
You can get it adjusted in the tune or try to crack open your throttle blade. There is an adjustment screw on the drivers side.
I just did a header, cam, intake, and carb swap. My AC use to work but doesn’t anymore. It’s a mystery honestly
Interesting. Could be a number of things as I’m sure you know. Troubleshoot…
I’m 99.9 percent sure it’s wiring. I didn’t cut anything out so I’ll figure it out
COOL yea have the ls on the phone how can i get it
🙌🏾
what are you useing to get your gauges on that tablet?
Torque pro app and an OBD2 dongle. The brand is BAFX off Amazon.
Excuse me, which is the sensor that controls the compressor off cycles, I did the swap, install the low-pressure sensor for the accumulator, install a relay and it turns on well, but the detail is that the compressor does not turn off.
The low pressure switch allows it the cycle. If you are running the R4, you need the high pressure switch and it has to be ran in series with the low pressure switch and tied into the power wire that turns on the compressor.
ruclips.net/video/zVqClRhrMyg/видео.html
Go to 4:00
@@MrGriffin23 So I have to take the signals from the pcm of the 5.3 engine ???
@@franciscomuros187 Yes, if u want to PCM to control the idle when AC is on.
@@MrGriffin23 Could you give me your number to send you a photo of a diagram that I have to see if it works for me I have been trying to fix that problem for a long time and I can not
@@franciscomuros187 DM me on IG: @MrGriffin23
Nice
Thanks!
MrGriffin23 Hey thanks to you guys like me can reference as we under take this task of swapping
MrGriffin23 hopefully I can reach out to u at some point
What r4 compressor did you get? I keep running through them
I think 4 Seasons brand or Murray’s from Oreilly’s.
I have a 90 caprice i need help to hook the high pressure switch up can you help me
I have a video talking about this will try to find it.
@@MrGriffin23 did you ever find the video on how to wire up the high pressure switch
@@lajames5067 ruclips.net/video/zVqClRhrMyg/видео.html
Fast fwd to 3:45. Hope that helps.
Hey man is it possible you could email me a schematic of how you wired your fans to come on with the ac, but still be controlled by the PCM, it has my brain scrambled and it’s driving me nuts lol
Are you fans already wired in?
MrGriffin23 yes, fans are already wired through the harness, just trying to have fans come on with ac but still be controlled by the PCM.
I don’t have one written out. I just followed some diagrams I found on RUclips. Here is a good video.
ruclips.net/video/Ckerl1Bk2jo/видео.html
Hope that helps some. I can locate a few others too if you need. Sorry if I’m not much help. I’m in the middle of moving and not driving the car much
What PCM are you using
Stock 2002 Tahoe PCM
What about 03+ pcm?
I am not sure. I would think an ‘03 would be fine.
The question is how you did you a/c on top
I don’t understand
Just joking, I'm having issues with my swap and we are watching videos all the time to see how people is handling the a/c compressor relocation and the speedometer.
Ruben Salais Gotcha! Yeah, I did it a budget way by using an old 90s style AC bracket. I wanted to dave money but a sure didn’t save any time. It was more work than I anticipated. I’d just used the ICT Billet bracket.
Speedometer, I just use my tablet and an OBD2 transmitter. Sometime down the road I’m going to get the Dakota Digital conversion box to have my regular speedo cluster work.
Did you wire in a relay for the compressor?
Yes
How did you wire it?
@@claytonhaske Too detailed to comment on, but you have to wire the high & low pressure switch in series. Also the power to the compressor needs to come from the climate control selector switch and it should have another lead going to a relay.
At least that’s how my R4 compressor is wired up.
@MrGriffin23 since the high and low pressure switches are in series. Do you have the relay before the pressure switches or after them, between the pressure switches and the compressor?
@MrGriffin23 so, it goes a/c switch(dash) to factory low pressure switch, the to the compressor high pressure switch(wired in series), then the relay, then the compressor?
What AC lines did you use?
1989 Caprice.
Hey Mr. Griffin do you still have the wiring of the pressure switch and stuff for the AC?
I'm shaping a ls into my caprice anyone turbo one of these an keep ac
Nice!
Mr G, do you have a part# for the belt you used?
K061265
It’s a loooooong belt. I wouldn’t run it again. I only did it because of the AC bracket I used.
So that belt won’t work with a dirty dingo bracket?
@@alvaroibarra469 I’m not sure of your accessory set-up. Are you running a Procharger as well?
I just put a 5.3 on my 94 Chevy truck and I was thinking on doing the same thing, using the ac bracket of the 4.3 but I guess I’ll just go ahead and order one on line
@@alvaroibarra469 It definitely won’t work if you are not running a Procharger. That belt was running that unit as well as all my other accessories. It will be too long. You should measure it to be sure with a ribbon or a piece or thin rope
Perry Cool think can do. for. my. car. G. Body
🙌🏾
Man I can’t even find my compressor wire cause everything is chop up
Should be able to trace from climate control too.
MrGriffin23 u know what color it would be?
Stateofsteezo The wires that go to the compressor should have a two prong plug. They typically had 2 dark green wires to one side of the plug and 2 black wires to the other side of plug.
Stateofsteezo 😭😭😭 i been on that boat
Help me plis
What you need help with?
How is the high-pressure sensor installed in the ac line? I already have my electrical connection from the ecm, only I don't know how the sensor is installed, welded or seva a special adapter, I am leaving the original compressor and the hoses
Francisco Muros I will look it tomorrow to confirm. If I can remember correctly, it’s hooked up in series with the low pressure switch. As far as you running your original compressor, I’m not sure if it’s the same.
Fast forward to 3:45. I explain how my high and low pressure switches are hooked up.
ruclips.net/video/zVqClRhrMyg/видео.html
Do you have a contact number I have a serious question about the ax wiring