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gammy 10-14-2008 10:20 AM

Help me to diagnose rough ride/engine/ issue
I am at my wit's end.

At low speeds, and especially under load..i.e on-road going up a hill, the engine misses and jumps...

If I floor it, it stops jerking...but, it may/will come back. Doesn't seem to be an issue at high speeds on the interstate.


I have had the local Jeep/Chrysler dealership look at the issue (had the vehicle 3 days) and a local shop (had the vehicle 2 days).
Nothing on the computer/diagnosis shows anything.

Distributor/plugs/wires changed (no help).

I had the exhaust manifold replaced back in the Spring? is that related?

Note: this has been going on for 6wks plus...I have tried gas additives, injector cleaners, ..



ky-homelite 10-14-2008 10:24 AM

Is it a manual tranny? Could the clutch be slipping?

gammy 10-14-2008 10:26 AM

Manual/standard 4-wheel drive.

Not sure of the clutch slipping...shifting is not an issue.

MOz 10-14-2008 11:02 AM

Perhaps your throttle position sensor is giving you trouble. It's possible the computer is not getting a clear signal throughout the range and this is leading to a driveability issue.

gammy 05-21-2013 08:24 AM

someone msg'd me on the side on the solution: SPARK PLUGS/WIRES, and I believe a Distributor cap.

workshop4ever 05-21-2013 09:47 AM

Could be time for new O2 sensors. The computer ignores them in high throttle conditions, but uses them at idle and low load. If you have an OBD scanner you can read the values coming from them to see if they make sense.... Otherwise could be TPS, IAC, etc.

ebilek231 05-21-2013 03:45 PM

i had baiscally the same issue with mine turned out i had a crack in one of my spark plugs

itscakes 05-21-2013 03:54 PM

Could be a faulty spark plug sounds like it might be firing to early and not at top dead center.

tkfx 05-21-2013 07:35 PM

Have you checked your exhaust mini cats? I'm not sure on your Tjs year but if you have mini cats, they could break down and block the exhaust holes causing the symptoms you described. It bogs the vehicle down under load, and also could cause rough idle. My cats went bad after 58k miles so I would definatly check those out too

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