Lost some time troubleshooting a drivability issue in the '90 Bronco. Started running rich but no codes. Took me a longer than im willing to admit, to figure out the ECU had failed.
In addition to the usual capacitor failure, we also had a resistor blow
A buddy fixed the ECU for me, but im my troubleshooting i replaced the injectors, assuming i had a sticky one. After reinstalling the ECU the bronco ran just as bad if not worse; some more troubleshooting revealed that one of the reman injectors had failed and was stuck open, just dumping fuel down the intake. So back apart she came:
I ended up putting the original injectors back in (the ones i had rebuilt myself about a year ago) and now its back to running just fine again! The moral of the story is, troubleshoot better, and dont assume the ECU in a 33 year old vehicle is still good!