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Bonneville wont start

Im not getting any spark at plugs. But my ICM flashes when i crank the engine. I replace to coils but still wont start. Could this be a weak crank sensor?

No spark on a GM = bad crank sensor or bad ignition module.


Those are the two most likely candidates. I would like to know what you mean by the ICM “flashes”…

I used a test light on the ignition moduel and then crank over the enigine. The test light flashes when cranking over the engine. I tested each spade connector.

I have never heard of that test. If your tach needle jumps or moves off zero when cranking the engine, your crank sensor is most likely good. This would almost certainly point to a bad ignition module, which is common on this engine. If it does not, the crank sensor and the wiring for it are good suspects. Do not rule out the simple stuff also, though, like fuses and bad or worn out secondary ignition components (plug wires, etc).

yeah! I saw this test at the wells manf. web site video. What u do is get a test light and connect the two spades with coils removed. The test light should flash meaning theres voltage on the primary side. Anyway, I got the car started by replacing spark plugs but that only lasted for a few mins. So, again no spark at plughs and the test light does not flash. Iam going to replace both ICM and sensor. Thank you very much for ur help. I will let u know what happens thanks