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Old 09-09-2014, 04:20 PM   #11
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if you are checking at the sensor with nothing plugged in you arent going to get anything out. if you check it plugged in you should be getting something there. its really a square wave but you should see a voltage somewhere in the middle not zero
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Old 09-09-2014, 05:40 PM   #12
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Well I made somewhat of a breakthrough. I must have been mistaken as to how the sensor works. The 7v signal comes FROM the ICM, instead of going to it. So that means that, when I was not getting a signal, it was because there was a problem with the ICM, not the CKP sensor, right??? This wouldn't have anything to do with the ECM would it?
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Old 09-09-2014, 11:23 PM   #13
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No the signal comes from the crank sensor to the ICM.....the crank sensor has to be in the circuit with the ICM to produce a signal......what you have to do is pierce the signal wire going from the crank sensor into the ICM, to get a reading.....there are two wires from the crank sensor....the 18x, and the 3x(synch signal)........so if you pierce the 3x line, and attach a voltmeter, and turn the key to "on", don't crank......now rotate the crank bolt, manually, one complete revolution(put a chalk mark on the crank pulley).......your voltage will be high, and then drop when a window(vane behind balancer) exposes the sensor.......this will happen 3x'* in one revolution....if you pierce the 18x signal, and rotate the engine manually one revolution, you will get a low/high reading 18 times in one revolution....

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Old 09-10-2014, 12:09 AM   #14
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Thanks for the info, but you seem to be incorrect. All the articles I have read agree with what you are saying, but you aren't actually testing where the voltage comes from. I found this out by removing the plug from the CKP and testing all the terminals from the ICM. I performed all the tests and more as you suggested already, and always pointed to the CKP. However, I got the 12v hot, but also showed 7v from both of the signal wires coming from the ICM. This test was performed cold, and started both before and after this test. I therefore assume that the way this sensor works is as the windows pass, the CKP interrupts (grounds, showing 0v?) the signal coming FROM the ICM and determines RPM/fires plugs/etc.

Long story short, I replaced the ICM and seems to be working for now. I idled it for 30 minutes now and restarted every time I tried. I will post updates if anything changes. Thanks again for all who tried to help.
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