just bought this camaro and have some issues. it was broken into before and they couldnt start it but made a mess of the steering column. the previous owner tried his best to bypass the VATS since it got screwed up, so in order to get it to start he put a pcm from a truck in it. it starts, runs, and drives fine. it has a high idle and the ses light flashes contantly. the electric fan doesnt work unless i have the a/c on and the airbag light is on (trucks didnt have airbags or efans). the pcm number is 1227747. through my quick search it looks like this could be a pcm from a 350 truck, i have a 305, so im sure its not running optimal, i know the gas mileage is horrible and it smells of fuel. so its probably trying to pump all this extra fuel thinking its a 350. so now that you know the history heres my questions:

1. What computer do i need? he said the old computer was in the car but its not. and does anyone have any spare ones? i know some people upgrade theirs to like syclone pcms or something.
2. i know he did all this wiring mess to try and bypass the vats (theres resistors handing down lol). and he told me he tried to wire in some vats bypass module and messed with the wiring harness. i need a schematic of the wiring harness that goes into the computer because of all the cut wires and wires hanging down. if anyone has that i would appreciate it.
3. i just got a good steering column with keys and vats module. i want to install this, but im afraid when i do it will screw up whatever crap he did and it wont start. the wipers dont work and the brights are stuck on do to the broke column so i want to install this but am afraid that ill have to rewire the whole thing and have a new computer on hand before i can start it again. im hoping i shouldnt have a problem with the truck computer.
4. does the flashing ses light mean the truck computer is shot? it does this with the ignition set to on or with the car running. not that it matters since i need a new pcm anyway but im thinking it could be the wiring.

I appreciate anyones help.

 

This isn't the proper forum for this, but I'll do my best to help out.

If your car is a TBI/Auto car, then I have an extra ECM/Memcal I'll sell to you for $35 shipped. PM me for additional info if interested.

Swap the column over first. Then see what happens. The vats module is behind the dash on the passenger side. You'll need to pull the console out, so you can wiggle the dash away from the car to get to it. Then you'll be able to assess what was cut and what wasn't. It sounds like you may be learning how to solder soon.

The SES is flashing since the car doesn't recognize the the car. I'm sure the wiring is slightly different for that ECM. The truck ECM doesn't have controls for the e-fan, and other small things. I'm surprised it runs at all.

Good luck with it.

-jason

 

oops sorry about the wrong forum thing, i couldnt decide where to put the post. maybe a mod can move it to the right forum? whatver that might be
(electrical forum?).

ill send you a pm on the ecm.

yeah i know where it is, i just need some diagrams to make sure the wiring is right. i learned how to soldier a long time ago, definately not a newb mechanic/electrician, just installed an aftermarket cd player last night in it (simple as pie).

yeah ive read that the truck pcm is wired different and thats probably what the wiring mess is by the ecm. believe me im surprised it runs too, runs good at that besides the gas mileage (it needs a tuneup which could be most of that).

just found this: Service number 1227747 was used in GM light duty trucks between 1987 and 1991 with engines 4.3L V6, 5L V8, 5.7L V8 and 7.4L V8 with automatic or manual transmissions.

so i dont know if the ecm i have is from a 5.0 or not. or even if its for an auto at that.

so you think if i get that ecm from you, put the new column and vats module in, fix the wiring mess that i should be good to go?

 

I moved your thread to EFI & ECM. As for the fan and the airbag, these have nothing to do with the ECM. They are completely separate.

For the fan, passenger side head, between cylinders 6 & 8 is a switch. That controls the fan on/off for temperature.

The airbag may be disconnected. Be careful of that thing, if it goes off it can easily kill. There is a connector at the base of the column that may be pulled, ir the DERM is bad.

The flashing SES: the previous owner may have put the PROM from the original ECM into the '7747, which won't work. The ECM will be in limp mode (real limp mode), and is why it runs rich.

If you can get a stock PROM for a 5.0l truck that used a '7747, that would probably run OK (even a 5.7l PROM would run better then limp mode).

You can also get an ECM (the 1228746) from a Caprice, no VATs. And the '8746 is the stock ECM for your vehicle. Then if you want VATs back, get the correct PROM and swap that in.

RBob.

 

thanks for moving it ah ok im used to the obdII world.

ok i will check this switch. i did read about this but i also read some places that the computer sets the switch on temperature but it was probably for tpi motors.

yeah the airbag light is on, if i disconnect the wire will i still have the light on? its probably already disconnected. i will be careful with it, pulling the fuse and disconnting battery, etc.

ok that makes sense with the flashing ses, im sure thats what he did. so if i get the 8746 ecm + memcal and hook up the new column, with matching vats module/keys, fix any wiring, replace my fan switch or just use a manual switch i should be good to go right?

thanks again for everyones help!

 

I'd hold off on fixing the fan until you get the correct ECM/Prom in the car. Then see if it works. Like I said, the trucks didn't have e-fans, so they have nothing to turn them on. Its not in the programing so to speak.

I'd swap the column now, then start repairing any wires that you find cut or spliced. I'll get you the ECM as soon as I can.

Good luck

-jason

 

thanks guys.

anyone have a wiring diagram for the ecm?

 

So where are you at with this now? I know the ECM was delivered last week. Was hoping to hear something about it running by now

-jason

 

wasnt able to do anything over the weekend with fathers day and my brothers wedding. hopefully tonight i can replace my steering column, track down all the wiring mess and put the new comp in and hopefully get it started. i tried real quick to put the comp in this morning for the heck of it and it would turn over but the injectors wouldnt fire. switched to the truck comp and it fired right up. so hopefully with the new steering column/vats module the vats will work and it will start up.

 

Alright, well keep us (me) posted

good luck with it

-jason

 

well im trying to put the new column in and the bottom plate that mounts to the firewall is not aligned the same in the replacement column. is there any way to turn it? it seams like you can but i tried to turn it and nothing, tried removing whatever i could and nothing as well.

 

all 3rd gen columns have the same mounting flange. Are you sure its a 3rd gen column? It should be triangular in shape..... two bolt holes on the side, and one at the bottom. Pretty straight forward honestly.

-jason

 

yup its from a 91 camaro. every single part of the column matches my old one to a T, even has yellow paint for the turn signals, the whole bottom half of the column is turned about 30 degrees. if i lined the bottom triangle up with the flange holes, then the middle two bolt wholes/mounting area is angled down 30 degrees. i cant figure it out there has got to be some way to rotate the housing. usually if you look at the column straight on, the two bolt holes in the middle line up perfectly with the triangle and this one doesnt.

 

moving this to a new thread to get some more help.

https://www.thirdgen.org/forums/tech...-steering.html


cant get this link to work for some reason, just copy and paste in browser.

 

http://chevythunder.com/fuel%20injection%20history.htm It helped me alot!