I have a 1988 Chevy S-10 2WD pickup with a 2.5-liter Throttle Body Injected engine. With the key on and the motor off the injector injects gas and floods the motor so it won't start. It does this intermittently. Now I can't get the gas to inject at all. Do you have any idea what the problem could be?
We have a couple of possibilities, but the problem should be easy to find. It could be that the injector itself is not seating properly. So when you turn the ignition on, and the fuel pump applies pressure, the fuel leaks right through the injector and floods the engine.
However, logic would have us lean more towards an electrical condition seeing that the injector has now quit altogether. The light blue wire leading from the fuel injector to the Electronic Control Module (ECM) could be pinched, or exposed and grounding out, causing the injector to open intermittently.
But we'll finish off with the most likely cause -- bad ECM. Go locate the Electronic Control Module under the dash on the passenger side, and tap on it lightly with the blunt end of a screw driver. While performing the "Tap Test", after keying up the ignition, observe the injector.
If it's spitting fuel in rhythm to the beat of the screw driver you've confirmed the ECM to be at fault. If nothing happens it will require a schematic and a voltmeter to isolate the problem, but it may still be the "injector driver" within the ECM causing the problem.