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post #5 of (permalink) Old 07-03-2007, 09:34 PM
I Might Just Know What I'm Talking About
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The engine can still be turning over and the tach read 0....What would tell me is that the signal to the tach is gone. On most engines this is the pulse to the coil to fire it. The tach is basically a frequency counter calibrated for the # of cylinders.

Yea, I agree with Taz, I don't think you have found it. The MPI system is pretty basic...CPS and TDC sensors basically run the engine. Everything else is there to fine tune the performance. If I remember correctly, once the engine has started, it does not need the TDC sensor in the runs off the CPS. But, if you loose the CPS...dead....the computer will stop all ignition activity.

I believe your CPS is down on the harmonic balancer. I would check it's mounting and break/make the connector a few times. your MPI OBDI? If so, I have an OBDI scanner...but we might need to get the Mopar connector...not sure if it is the same as the GM are more than welcome to try it.

Otherwise, short out pins 1 and 2 and read the codes. You can sometimes have a code but it won't set the light.

AKA DDawg16
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