Sputtering, I have replaced the IAC, TPS all six plugs and coils?

2005 JEEP LIBERTY
223,000 MILES • 3.7L • 6 CYL • 4WD • AUTOMATIC
Avatar
JOSHUAMO2
  • MEMBER
  • 2 POSTS
I have replaced the IAC, TPS all six plugs and coils, PCV valve o2 sensor and I am still having intermittent start issues and bogging out low power low fuel mileage no vacuum leaks I can’t seem to find the issue all plugs are gapped at vehicles specifications.
Sep 26, 2022 at 2:08 PM
Advertisement
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
It sounds like the engine is misfiring, but I can tell for sure if you upload a short video of the engine cranking, and then running. In the meantime, please run the codes.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Also, with this many miles we should do a compression test which you can rent the gauge from the auto parts store for cheap.

https://www.2carpros.com/articles/how-to-test-engine-compression

Take note of what the spark plugs look like compared to each other. This can be a clue to the problem cylinder.

Please go over these guides and report back.

Sep 26, 2022 at 5:01 PM
Avatar
JOSHUAMO2
  • MEMBER
  • 2 POSTS
I ended up finding out #5 was misfiring without a code thrown until I turned on the A/C one of my new coil packs was intermittently failing.
Sep 26, 2022 at 5:58 PM
Advertisement
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
It happens, thanks for getting back to us. Use 2CarPros anytime, we are here to help. Please tell a friend.
Sep 27, 2022 at 12:31 PM