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Misfire? Fuel-pump? Oil pressure?

Discussion in 'Wrangler TJ (1996-2006)' started by GrizzliAtoms, Mar 15, 2017.

  1. Mar 15, 2017 at 3:33 PM

    GrizzliAtoms [OP] New Member

    Mar 15, 2017
    2002 4.0L Wrangler TJ Sport
    31 x 10.5 Wrangler Tires, KC Daylighters mounted to hood (disconnected a.o. 3/2017)
    I will give the full story to try and get the most accurate help that I can. My Jeep has been bucking on and off for several months but I wouldn't even say it happens 50 percent of the time. Today it escalated to an entirely new level.

    Started it up and drove about 3 miles and the whole time it would buck no matter what rpm I had it to or what gear. Noticed that the oil pressure gauge was at about three quarters of the way to max (80). It struggled much more when travelling uphill.

    Upon trying to leave the destination, Jeep on clicked upon turning the key. I had recently replaced the alternator because the terminal post on the previous one had practically welded itself to the terminal- ruining both the post and the terminal end. Since there was no threading and I was at work, we rigged up a set of gator clips to the post instead of using the proper gauge end. It has held up fairly well so far.

    I tightened the clip and made sure that it had a good bite and it started right up. At this point, however,from point B back to point A, it bucked much more and the pressure became maxed out at about 1.5 of the 3 mile trip.

    I let it sit for a while while I got ready for work and when I started it up, everything seemed fine aside from minor bucking. During the 10 mile trip to work, after about the first 2 miles, it bucked just as bad as the second trip and really struggled to accelerate. Hitting around 3krpm, would cause it to drop off sharply as it would when you reach the normal limit at around 5 or 6k. During this trip, the CEL also flashed. The oil pressure gauge stayed at around 3/4 to max the whole time and all other gauges are normal. Good temp, good charge, half of a tank of fuel from a reputable truck stop, etc.

    I am sure that there are a couple of issues that are hitting simultaneously, but I am most concerned with the consistent bucking and the high oil pressure reading. I saw a couple of other threads on here that ere similar, but I wanted to make sure that I provided as much information as possible.
  2. Jun 26, 2017 at 8:26 AM

    Pcchadwe Member

    Jun 26, 2017
    First Name:
    2005 TJ Rubicon
    4" lift, headers, stainless steal cat back system, 33" wheels, 9.5ti Warn winch, cold air induction, gel battery, crawler bumpers, lifted induction,
    What engine codes is it throwing? Should be P0340 or P0344. If the oil pressure is acting up also, it may very well be the oil pump drive assembly. It controls the spark distribution to the ignition rail, like old distributors, and drives the oil pump through a slotted connection at the bottom.
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