Random misfires

2006 JEEP LIBERTY
219,000 MILES • 3.7L • V6 • 4WD • AUTOMATIC
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MASHCRAFT1969
  • MEMBER
  • 2 POSTS
New plugs, coils, injectors, cam sensor, crank sensor, TPS, ASD, transmission, ECU. Still random misfires!
Jul 29, 2019 at 2:18 PM
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SCGRANTURISMO
  • CAR REPAIR CONTRIBUTOR
  • 4,897 POSTS
Hello,

Can you please check for any vacuum leaks, especially around the intake manifold. A vacuum leak is notorious fire causing misfires, random misfires, and a whole list of other driveability concerns. Here is a link for you to go to below:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Please go through the guide and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros
Jul 29, 2019 at 10:48 PM
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MASHCRAFT1969
  • MEMBER
  • 2 POSTS
I will check Friday afternoon and get back to you. Thank you.
Jul 31, 2019 at 11:53 AM
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STRAILER
  • CAR REPAIR CONTRIBUTOR
  • 54,354 POSTS
If I can jump in here, I have seen the MAP sensor do this I would remove it and see if it holds vacuum here is the location. Check out the diagrams (Below). Please let us know what you find.
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Aug 2, 2019 at 3:59 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.