1990 G20 5.7. Overdrive trans.
I have no check engine light when the key is turned on. I can't get the light to work by jumping the pins on the obd plug either. The bulb is good. The grounds at the thermostat are good. I have put all new sensors and ECM on the car. I just put in a new distributor too. The van runs but it has a intermittent erratic shifting when under load. No power sometimes too. Any help with the check engine light may put me on the right path to solve this. Also has new fuel pump and filter. Thanks.