Hey Gang,
Just purchased 1987 IROC Coupe 5-speed TPI.
Came with receipts for motor rebuild (10k ago) Within the last 5,000 miles car had a Performance chip installed along with new Distributor and wires (red color)
Problem is the car is running rough... Really sounds like a bad plug or wire but reading this board also makes me think the chip may be faulty. No smoke from exhaust but it smells REALLY rich and car runs very cold - Below 1/4 mark on temp guage.
I will pull and inspect all plugs and wires tomorrow.

Code Scanner turned up no error codes. Just code 12.

Any other info would be appreciated! I am new at this!!

Thanks,
Sean
87 TPI 5-Speed with G92 (3.45)

 

code 12 just means that your diagnostic system is working...so that could possibly mean that something mechanical is messed up, and that something is not in the engine diagnostics.

 

In my experience all those chips do is give you bad gas mileage. That may be why you are running rich. You may want to check and see if there is coolant in your cooling system, it may just be water(pure water cools better, but doesn't have the desirable characteristics that we use coolant for). Our instruments are known for their innaccuracy, though. You may also want to check the timing, and make sure everything was installed properly.
Hopefully those red wires say 'MSD' on them

Congratulations on your purchase, and welcome aboard!

 

if it's not throwing codes you can pretty much rule out something going wrong in the TPI system..

I would try to narrow it down to the basics:

is it mechanical, yes or no
if it's mechanical, how can i read the parts that i check (plugs, distributor parts)
if it's spark, where could the spark go bad
if it's not spark and not mechanical it's got to be fuel
if it's not fuel, it has to be something ECM related (which would throw codes)

think of TPI like this: it's just a standard small block chevy with a very high performance carburetor on it. if you can narrow out the sbc part, it's just the high performance carb you have to deal with..

good luck man!
Colin

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Webmaster: www.IROC-Z.org

 

Temp could be an issue, the ECM lives on the coolant temp...
Looking at the plugs would be a good start, as well as doiong as much "visual" troubleshooting as possible (cap/rotor, etc). Might be a simple fix, might involve some deeper troubleshooting.

 

I could almost guarantee that there is a 160 degree thermostat in there. My guage read very low when I had one in mine. Probably was put there because of the chip.