Misfire when idling

2007 JEEP CHEROKEE
230,000 MILES • 2.8L • 4 CYL • TURBO • 4WD • AUTOMATIC
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SYBRANDT VAN WYK
  • MEMBER
  • 1 POST
Drives fine at 40km. Fuel injectors all fine, been tested.
Compression test: Cylinder 1, 2 and 3 is fine 20 bar but Cylinder 4 is low at 12 bar.
what could the course be?
2.8 CRD.
Oct 5, 2020 at 8:28 AM
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KASEKENNY
  • ✓ASE Certified Mechanic
  • 18,907 POSTS
  • ASE Certified Mechanic
We need to do a cylinder leakage test. This will tell us where the compression is leaking causing the low compression.

You will need a cylinder leak tester and then set this cylinder to top dead center on the compression stroke and then put about 20-40 PSI to the cylinder and see how much air is leaking. Then you need to go to the tailpipe, engine oil fill cap, intake hose, and coolant bottle to see where you are hearing or seeing air escape via bubbles in the coolant.

This will tell us where the compression is escaping. Let me know what questions you have. Thanks
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Oct 5, 2020 at 5:39 PM
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