QuestionIn response to your answer. Yes there is battery voltage at all times to injectors, icm, pcm. It has spark just no injector ground by the pcm.All grounds and hots to pcm check good. The tps reads fine.Somthing seems to to be screwing the signal from the icm to pcm even though the wiring checks good. Do you know what the signal the icm sends to pcm? There are 3 wires that interface. Any other ideas? thanks Randy
AnswerHi Randy,
I'm not great in the ECM inputs, but I believe the ignition control module sends crankshaft position information to the ecm, which in turn sends injector signals, as well as operating the fuel pump relay, and electronic spark timing also I believe.
Note that the fuel pump will also run as soon as oil pressure builds to at least 4 PSI, so it would run with a bad ecm.
I don't have access to the orriginal question, but seems you said you replaced the icm in the distributor. Did you look real close at the wires?
Another thought...does that engine have a crankshaft position sensor down beside the crankshaft damper pulley?
And try to start it with the throttle position sensor unhooked. There is a clear-flood mode on some engines when the gas pedal is held to the floor, but it comes from the tps, so that might let it start on default.
Van
