No spark

[Joe Dirte]

This might be a silly question, but is the crank position sensor reluctor wheel still on the crankshaft? Asssuming you had the motor out and rebuilt based on everything else. It would be under the timing cover

Its in there. I changed chain just to be on safe side n made sure to leave wheel there.

 

[east302]

So the code stems from the VCM not getting the signal from the CKP sensor within half a second. Assuming you don’t have the $Kent $Moore tool referenced in the diagnostic table, it wouldn’t hurt to check for continuity in the two lines from the sensor to the VCM.

Disconnect C1 from the VCM and the connector at the CKP. Take a meter, put it on the tone setting and put a probe at the ends of the yellow wire. Repeat for the purple. Wiggle the connectors around while checking and see what happens. Hear a tone (or see near zero ohms resistance) and you’re probably good on the wire and connectors.

Ideally, though, you’d be backprobing that yellow wire while it’s connected to the CKP and see if you get voltage while cranking. Rigging up a small lightbulb instead of using a meter may be easier to manage.

Others may have some ideas as well.

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Pins 31 and 28 are from the CKP:

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[Jason Hackett]

1998 k1500. 350/4L80e. Was a full build project that i havent posted yet. Everything electrical is hooked up, have all grounds connected. Not getting spark. I was able to probe the white wire on ICM n hooked to battery it would fire. Did continuity tests in wiring and everything is good to go. Battery fully charged, couple gallons of gas, gettin 60 psi. So fuel isnt my issue. Anyone else ever ran into this? Oh and keeps throwin CKP code but thats new (4 different ones) and install was good. Im at a loss.

Also should my tach be readin when i crank it? Scanner isnt picking up any rpms when i hit the key.

Tried another pcm too n still same issues.

I

 

[Jason Hackett]

I had same problem. Check your ground or run a new one to ICM.

 

[Joe Dirte]

I had same problem. Check your ground or run a new one to ICM.

Was it throwin a crank sensor code?

Update we are gettin voltage from ckp.