fltche1

Ok i have determined that the IAC circut on my ecm is bad. that is why my car keeps dying on me. I am wondering a couple of things... What is the number i need to look for on a replacment ecm for a 1986 Trans Am with the 5.0l TPI? Second is, can i get my ecm repaired? if so what is the general price range for such a job? What is the best option here guys?

fltche1

and do you guys know of any good places to get a new ecm?

vetteoz

iTrader: (13)

# 1227165 ECM used on many GM '86 - '89 cars .The chip ( memcal ) which you swap from yours into a replacement ECM is what determines what it suits
Service number may be different if rebuilt or over the counter replacement
Several places offer rebuilt / exh units
https://www.thirdgen.org/forums/engi...d-165-ecm.html

fltche1

and just out of curiousity... have you ever heard of a hyperchip? would that fit in that slot there in the ecm? and do you know if that chip can go bad? the original?

ploegi

Hyperchip is an aftermarket "performance" modification. In reality, it is snake oil, and does little or nothing. It IS possible for the prom to go bad, but, that is a very rare thing indeed.

fltche1

i see. obviously cappacitors in the ecm go bad and leak and disable functions on the car frequently after about 175000 miles or so? Cause it sounds like a lot of people run into that problem. or the cappaictors just go bad.

fltche1

Does any body know where i can get ahold of a new SVC# 16198259 ecm? either that or i need a general idea of what types of places repair them.

ploegi

Repair? Not sure that anyone really does that trick on an individual basis.... you should be able to get one from any parts store, and they will want your dead one in exchange. (plus, some cash, of course...) You could also possibly find them in junkyards.... the same computer was used in a fair number of applications, just gotta swap your chip in there.

transam85dudeman

for a computer, go to autozone now. for a chip, for to a local chevy dealer. i had my computer fail after surging the voltage. Replaced it and 4 months later the computer fried again, (reman computer) it smelled like gram crackers in butt crack. eww. replaced the ecm, chip, and memcal and was back in business. i dont think a iac is bad on your car. test the ecm by enabling the diagnostic mode. also another quick check is to turn the key to on. is the check engine light on? if not..then the prom/ecm is bad.

Chevy86 IROC-Z

iTrader: (17)

Remanufactured ECM from Cardone at Kragen. $79.00

http://shop.oreillyauto.com/ProductL...pe=248&PTSet=A

fltche1

I have interesting news for all of you... i replaced my ecm with the cardone ecm from shucks orielly... I used a 12 volt tester to make sure i was getting power from the ecm to the IAC. we did not get power on 2 of the wires. terminal a and c. which would be the blue with white and the green with white. we then tested right up to the ecm. still nothin. that determined that the ecm was bad for that circut. we replaced the ecm and now the green with white passes the test. so i test the continuity on the blue with white. i have continuity.... im stupmed... what else could it be?

Chevy86 IROC-Z

iTrader: (17)

Okay, problem not solved right? First disconnect the battery for about 2 minutes. reconnect battery. Follow the instructions here on this page provided. It explains how to tune up your TPI. http://74.125.155.132/search?q=cache...&ct=clnk&gl=us

Once you tune the Camaro, take it out for a drive. Floor it, cruise it, then park it. The point is you want put the Camaro through a battery of tests so that you can pull out every Trouble code as possible. Now ground your ADLD to display any trouble codes if any. Note the code and post it here so that we can further assist you. If you choose not to do the test provided above, then explain exactly what is going on and when it occurs so that we can pin point more less when and where the trouble is occuring. Example; if your driving and you let off the gas peddle, the motor begins to sputter and eventually dies. One common problem to this a vaccuum leak. Solution: Turn on Camaro and spray all the gasket areas on the intake (runners, plenum, intake manifold). If the idle begins to go up considerably, then you have located your vacuum leak. But please do exlain what the issue is so that we can figure this out.

fltche1

here are the tests i have done so far. So far i have tested the whole mass air flow system, the mass air flow relay, the mass air flow burn off relay, the wiring, the connector that plugs into the mass air flow sensor, the mass air flow sensor has been replaced, I have adjusted the idle multiple times, i tested the egr and fixed my vacum leaks in the hosing itself. I have a replacment egr soliniod. and i currently have the lines closed off for testing, i have replaced the ecm, i have tested the wires for continuity between the IAC and the ecm and i have continuity... i have used a 12 volt tester between the ecm and the IAC and i have voltage on all the wires except for the light blue with white that runs from the IAC to the ECM. My problem is that my car when you decellerate will surge if that makes any sense. you let off the gas and then it acts like you are accellerating and then lets off and slows down again. Even when you are cruising right at 55 mph it does this too along with certain other speeds. but if you leave it sit idleing the rpms go up past 1k and drop back down and then they go back up to or past 1k and then it keeps doing this and eventually sputters out and dies. the code i have is a code 33. Im out of ideas... I also tested all the injectors and they were all within spec.

Chevy86 IROC-Z

iTrader: (17)

Obioulsy your getting more fuel when your not supposed to. maby your injectors are going bad or the pulse that is sent to the injectors is staying on a little longer which would result to more fuel, thus giving you acceleration instead of de-acceration. Thats what I think. There should be a better explaination. Anyone else got anyother ideas?

fltche1

well i am not sure that it is too much fuel. Because my speed does slow down but it is weird that it surges the way it does. as my speed slows the surges seem to become less powerful... then they fade completely at about 50mph its like its going inbetween gears or something but i know it isn't stuck imbetween gears. And i know that there is an issue with fuel delivery but i don't know what area... my intake doesn't have a leak so that one is out.

fltche1

But i have already tested the injectors and they are all within spec.

vetteoz

iTrader: (13)

Is your VSS connected and working properly?
If the ECM doesn't see the road speed drop it will not pull fuel out on deceleration

DFCO deceleration fuel cut-off.
"is when the computer shuts off the injectors (pulse width equals zero) when slowing down. There are several parameters that must be met for it to be enabled and several more to remain in DFCO, mostly relating to vehicle and engine speeds, LV8 or MAP value, and %TPS."

https://www.thirdgen.org/forums/diy-...confusing.html
https://www.thirdgen.org/forums/diy-...-dfco-bad.html

fltche1

ok... would that affect my idle though and account for why my engine keeps dying in park or when i am sitting at a stop light when im driving?