92 rs car will not start or run with prom chip installed will run without however not correctly gm says it is a bad prom however i've bought two proms both ecms and proms work in another car. can you help?

 

Is the 92 rs a 305 w/TBI or a 3.1l w/MPFI? By your description sounds like a TBI setup.

Couple of items to check for: use one of the ECMs and the PROM that worked in the other vehicle and install it in the car that doesn't start. While watching the SES light turn on the key (just on, no cranking). Did the SES come on, blink off and come on solid? If not is it on solid (no blink) or not on at all?

If it does the blink then hook up a scan tool and check the sensor values. Do this with the key on engine off. The TPS, CTS, and MAP are important and need to be correct.

RBob.

 

Sounds like a possible VATS issue.

The software that checks VATS for fuel enable is in the EPROM.....if you have a VATS problem keeping fuel disabled then the ECM won't fire the injectors, but if the EPROM is out it won't even check VATS and will run in limp-home mode.

This is all assuming the starter enable relay has been removed/bypassed, as it operates directly off the VATS module and will keep the engine from even turning over.



Just a brainstorm.