Car is an 86 trans am with a fresh built 350 with the stock tpi intake and 24 lb bosh 3 injectors 9th injector and egr delete tuned memcal with 89 programming and a afpr

I just bought this car with a knocking 305 and dropped a 350 in it. The car is running pretty good but my ses light is on and I tried paper clipping a and b and got nothing so I went to the parts store to use their scanner and no communication. So I wiggled all ecm wires and checked the volts on pins a and b and I have always had 5 volts.

Any suggestions?

 

I would say get a replacement ECM

 

If you're pretty handy with a voltmeter and mildly familiar with electrical wiring, I'd recommend running through this electrical check before replacing the ECM. Make sure your current ECM is getting all the right inputs to begin with. Otherwise a new ECM will give you the same issues.

http://chevythunder.com/fuel%20injec...cm%20#1227165)
ECM Pinouts

Basically, one meter probe on battery ground, then take the other and start back-probing the connectors at the ECM.

 

Thanks for the useful link! I am having my friend who is an electrical engineer help me test the wires according to the article and I will repost our findings . We both are starting to believe there's a wiring issue going on.