Vannin' Home Forums General Discussion Electronics Bad ecm? (1989 350 tbi)

Hi.

1989 chevy g20 350 tbi.

Car is pretty new for me. When i bought it, SES light didn't worked. Now i have tested bulbs and wiring. Brn/wht wire from ecm to SES light didn't ground. I opened ecm and soldered all pins and components, no effect.

How i can be sure that its ecm?


Icm has been bad two times too, 5v signal loses and it wont give pulse to injectors. Has been fixed with new icm allways.


Coil is new too.


I don't know are those one or two faults but i want that diagnosis to work.


Thanks

I hope you used heat sinks when you soldered all the pins.....

A bad ECM will usually not throw any codes Are any codes showing ? If not, disconnect something to provoke a code and see if it registers.

I had an 89 caprice police car one time that I couldn't get to show any check engine light when I shorted the terminals, turned out the ecm was bad due too the TCC solenoid shorting out and it burned up a chip inside, but still ran fine, Swapped PCMs and unplugged the transmission connector and everything was fine.