TPI HELP
 

I have a 91 Z28 and it has a rough idle problem and after the car warms up it will not start,eventhough I have spark. After the car cools down it starts fine. It only has a rough idle after it goes into close loop. I have replaced the following items:
oxygen sensor
distributor
spark plugs
spark plug wires
egr
TPS sensor
MAP sensor
cleaned throttle body
I also have a fuel pressure gauge and pressure is holding. I am starting to think it is the ECM since it gives me problems in the closed loop operation. Any ideas would be great.
Thanks Jason

may be 2 unrelated problems... starter may be getting tooo hot, rough idle could be a ton of things... dirty idle air control motor (IAC), dirty throttle body, a bad plug or wire... start with looking over EVERYTHING really close

I cleaned the IAC and throttle body and the spark plug wires are brand new.

I forgot to say the motor cranks but will not start.

i had the same prob with a 88 gta tpi i changed the ecm,spark plugs ,wires ,cap rotor,coil,iac,o2,all it was was a dirty fuel filter

I replaced that also. Thanks

get a noid light see if the injectors are firing.

I was thinking of doing the noid light. Thanks

do you have any codes? know what your fuel pressure is? If you havent done so, these are always things you should check before throwing parts at it. I had a similar problem that i traced down to my ECM being bad and it was the distributor having one stripped hold down screw. A

No it has no codes and , I have a gauge on the fuel rail. There is no gas coming out of the vaccum hose attached to the adjustable regulator so the regulator is good.

when you jump the aldl terminals do you at least get it to flash code 12 to start with?

Yes, that is the only code I get.

Well, today I ohmed my injectors and 2 are bad. Number 3 injector was only 7.9 and number 4 was 8.0 when it should be 16.0. I ran the car to operating temp. and check the 2 bad injectors, the readings drop to 5.8 when they are hot. I was thinking of replacing them with Racetronix injectors. Any opinions?

replace all 8 not just the bad ones

Yeah, I was not only going to replace the old ones. I am going to replace all 8 since there are 19 yrs old. Has anyone used Racetronix injectors?

i have racetronix ones, no complaints