coil packs will not fire - no spark?

2004 CHEVROLET SILVERADO
418,000 MILES
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BULLET07
  • MEMBER
  • 1 POST
the coil packs will not fire i changed out the crank shaft sensor but still no fire. what else do i need to check the fuel pump is also ruled out do to it is holdong approxmatly 55psi which is reccomended for this vechile
Sep 17, 2013 at 3:55 PM
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SQM
  • ✓ASE Certified Mechanic
  • 6,383 POSTS
  • ASE Certified Mechanic
Hello,

It sounds like you might have an issue with the ignition control module.
If you are not getting any power to the coil pack, you will need to check the ICM.
I would recommend you getting the ICM off and have it tested.
Just about any auto parts store have the ability to test the module.

https://www.2carpros.com/articles/how-to-test-an-ignition-system

I have attached the diagrams for your reference.

Please let me know of any questions.

Thank you.
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Aug 8, 2021 at 4:59 PM
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