Danny Schwartze

I am wondering if anyone could help me narrow down what might be causing my 1988 Camaro 305 TPI to run rich and sputter? Engine' has been rebuilt , new fuel tank, etc. I've seen posts on putting in a new distributor and replacing a small vacuum leak into the TPI. Didn't know if there were other common causes? Basically the car will run great for a while and then cut out, run rich while in idle or running 70 Mphs. Throws some codes. Seems to be worse when the engine is warm and happens randomly. Once did it while idling for 15 mins, next was after 2 hours of driving. After the 2 hour drive, continued to run rich and was un-drivable. Any help would be great. Thanks!

Aviator857

what codes does it have stored?

Have you verified the MAF sensor is good (85-89 TPI was MAF and 90-92 TPI were MAP) as well as the o2 sensor? These two sensors is what the computer uses to adjust the fuel curve. If the ECU is demanding the right fuel then its probably a physical issue and I would start looking at the fuel pressure regulator and/or stuck fuel injectors.

Danny Schwartze

Thanks Aviator857, both the MAF and O2 have been replaced. The distributor is next to be replaced and we're double checking a small vac line going into the TPI. I've read a bunch of treads and it seems this issue can be a big range of things. I read one mentioned a Coolant sensor might be the cause as well. Any other thoughts are welcome

Aviator857

I've seen 10 people over the last few months need new injectors because they were leaking out and causing rich condition or flooding the intake or sticking close making first start hard to impossible without starter fluid.

Also I've seen alot of bad new parts, if you have a good multi meter look up how to test the sensors and make sure the new ones are good. An exhaust leaked upstream and about 6 inches past the O2 can throw it off.

How are the plugs, gapped right?

You said running rich what are the indication, plugs, smog test, or just smell?

Aviator857

What brand fuel pump alot of the store brands and even acdelco are not as good as orginal. Put a fuel gauge on it and drive till it sputters see what the pressure is doing.

Distributor pick up and ignition control module can flare up when hot. If fuel pressure is steady when the issue is occurring I would look at ignition.