1996 C3500 7.4 No Spark from Coil
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1996 C3500 7.4 No Spark from Coil
Started with random dying when idling or driving but would immediately restart. Now it won’t start at all. Have confirmed no spark coming out of ignition coil.
ICM New (Delphi). Confirmed signal from PCM, 12V power with key on, Ground. All ok.
Coil New (AC Delco). Confirmed 12v power wire with key on, signal from ICM good and tach wire isn’t grounded somewhere (severed for testing purposes)
Crank Sensor New (AC Delco). Confirmed 12v power and continuity between VCM plug and pink and yellow wires. Also have RPM signal with scanner.
I have checked all fuses. Good. I have confirmed VCM ground at thermostat housing. Clean and tightened battery connections. Cleaned and tightened ground at FR side of engine block.
Fuel pressure good @ 55 PSI.
I am now lost at where to go. Everything to tell the coil to fire is there. It just isn’t. (Tried multiple coils and 3 ICM just in case).
Can the ignition switch wiring can any way shape or form affect the coil not sparking?
Ideas please before I sell it for beer money 😁
ICM New (Delphi). Confirmed signal from PCM, 12V power with key on, Ground. All ok.
Coil New (AC Delco). Confirmed 12v power wire with key on, signal from ICM good and tach wire isn’t grounded somewhere (severed for testing purposes)
Crank Sensor New (AC Delco). Confirmed 12v power and continuity between VCM plug and pink and yellow wires. Also have RPM signal with scanner.
I have checked all fuses. Good. I have confirmed VCM ground at thermostat housing. Clean and tightened battery connections. Cleaned and tightened ground at FR side of engine block.
Fuel pressure good @ 55 PSI.
I am now lost at where to go. Everything to tell the coil to fire is there. It just isn’t. (Tried multiple coils and 3 ICM just in case).
Can the ignition switch wiring can any way shape or form affect the coil not sparking?
Ideas please before I sell it for beer money 😁
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