Here is a doozy! (no start)
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Re: Here is a doozy! (no start)
If you're sure there is no spark, and you've changed all the ignition components, it's time to start looking at signals to see if they're there.
Start with the white wire going to the ICM. With a multimeter set to AC, when the engine is cranking, it should read between 1 and 4 volts AC. If not, ohm the wire from the ICM to the PCM. If so, check the black wire for a good ground and the pink/black and white/black wires for 12 volts. If that checks out, put a plug and wire on the coil and crank it over to see if you have spark there. If all the previous checks out and you still have no spark at the coil, it's DOA.
Nothing hard here, just methodical testing of one piece at a time.
Start with the white wire going to the ICM. With a multimeter set to AC, when the engine is cranking, it should read between 1 and 4 volts AC. If not, ohm the wire from the ICM to the PCM. If so, check the black wire for a good ground and the pink/black and white/black wires for 12 volts. If that checks out, put a plug and wire on the coil and crank it over to see if you have spark there. If all the previous checks out and you still have no spark at the coil, it's DOA.
Nothing hard here, just methodical testing of one piece at a time.
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Alex Barnes
LT1 Based Engine Tech
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Jan 24, 2015 10:21 PM