hey guys, quick question about something ambitious that i want to try out. So, I had a bad ecm that was throwing me code 9. replaced it, everything is fine. Now i really want to find out which chip failed on the board. Does anyone know which component(s) inside of the ECM processes the information from the distributor and is it possible to replace it? There was no corrosion on the board and it looked in pristine condition, even my instructor could not find anything. Also, i found a link to a ECM diagram on wikipedia but it was not very helpful, so if anyone knows of a good diagram and can link/send it I would be very thankful.

 

Which model year is your car?

Cars from 1997 and before have failing electrolytic capacitors which can cause all sorts of weird symptoms and drivability problems...
The first course should be to replace all of those usually there aren't more than a dozen and with basic soldering skills they can be replaced
then test..I would bet that your failed ECU will be working fine again.

 

working from the ECU pinout/wiring diagram for the engine harness, identify the pins related to code 9 (or use pins called up in the FSM troubleshooting procedure) and trace it across the PCB. tedious but works for a lot of cases. search white pages for all related components on to get those pinouts too.