I have an 85 Vette that someone has repinned/swapped a 165 86-89 computer into. Car will not start and there is no communication via serial data. I am coming in after someone doing this so looking for some info on how to attack this. When you try to start it the cold start inector fires but no injector fire at all. Runs on ether. So what signals are needed initially in this ecm inorder to command prime or crank pulse? I figure this is the best avenue to try and figure out what has gone wrong. All suggestions are very appreciated. Hoping RBOB would chime in.

 

When the ecm is powered on the fuel pump relay is grounded and the pump will run for 2 seconds.
You don't mention what your using to communicate with the 165 ecm, a scanner , a paper clip ? The 165 needs to be put in 10K mode to read a data stream but it doesn't sound like your to that point since it has no injector pulse.
To get injector pulse is the icm purple/whit or bulk stripe wire hooked up to B5 ?
Do you have constant and switched power to the ecm ?
All grounds have been verified ?
power to the injectors ?
Memcal identified and vats eliminated or bypassed in some manor ?

 

Got it fixed after all that beating my head against the wall. Reburnt the chip and it worked.

 

What was the culprit? Do you have a log of the changes?

Just curious what happened...

 

Mentioned, bad .bin or offset!