Crank sensor testing?
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Joined: Jan 2003
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From: Jenison, MI (Near Grand Rapids)

I should have posted the fix before. Thanks for the reminder.
My issue was actually a bad physical ground between the ICM and it'* mounting bracket. There was too much corrosion between the two. As a result, the Crank Sensor wasn't being given a good "sensor ground", and it couldn't function properly and return a signal to the ICM. The voltage between the "sensor power" and "sensor ground" was very low... far below the 10v that the Haynes manual says it gets.
Cleaning up the bottom of the ICM and the top of it'* mounting plate restored good contact, and it fired right up.
Funny thing though: I tried another ICM and set of coils on it, to see if it those were the problem, and those didn't work either. It took some actual sanding to restore good contact.
My issue was actually a bad physical ground between the ICM and it'* mounting bracket. There was too much corrosion between the two. As a result, the Crank Sensor wasn't being given a good "sensor ground", and it couldn't function properly and return a signal to the ICM. The voltage between the "sensor power" and "sensor ground" was very low... far below the 10v that the Haynes manual says it gets.
Cleaning up the bottom of the ICM and the top of it'* mounting plate restored good contact, and it fired right up.
Funny thing though: I tried another ICM and set of coils on it, to see if it those were the problem, and those didn't work either. It took some actual sanding to restore good contact.


