I went out to start the car the other day and it started fine. So i shut it off and burned another PROM (chip ) for it. Put it in and it wouldn't start. So I put the firts chip in it and it still won't start. I tried my ECM in my buddy's car and it works fine. I also tried his ECM in my car and it still won't start. I have spark, and I'm getting fuel pressure at the schrader valve. The fuel injectors also have 12v. with the key in the on position. I pulled a spark plug and it looks fouled. Is it possible that it's so fouled that the car won't start at all?

 

Yes, it's possible to have plugs so fouled or wet with fuel that all spark is shunted to ground instead of jumping the gap.

 

Ok, thanks. I checked for spark (but it was with a spare plug I had laying around, not one of the fouled ones) and I have spark. I have fuel pressure at the schraeder valve. How do I tell if the ECM is firing the injectors? I have 12v. to them with the ignition on, but I want to know if they're being told to fire. I thought of using a voltmeter across the terminals of the injector plugs, but I seem to remember seeing somewhere that if you cross those terminals that the ECM could be damaged.

 

Nasty,

You could try to measure voltage at the injector terminal, but don't short the two leads together.

A problem with that is that the sampling rate of most meters (except a Fluke Scopemeter) is far too slow to detect the 4-6mS injector firing pulses. You can use a Scopemeter, a regular oscilloscope, or an injector test light (commonly called a 'Noid light) to check injector firing signals. The test lights are about $6-10.