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98 TJ 2.5 Engine / Misfire Issues


New Member
Feb 21, 2019
South Jersey
Hey Jeepers,
My 1998 Wrangler TJ 2.5L Auto has been giving me some issues while driving. Recently, the engine has been giving me a sort of lag as I accelerate, more specifically within the 35-50mph range. Also, when pushing gas and pushing past 3000rpms, my Check Gauges light would pop on, before jumping from 210 to 270+ and then back down to 210, with no Check Gauges light. wtf?
I pulled P0300, P0302, and P0303.🤬
I'd also like to note that the head gasket was replaced about 15,000 miles ago, and the throttle body was recently cleaned. Before trying to get at it, I'd like to see if anyone could point me towards the right direction. Maybe a head gasket? again? (please no)
Any help would be greatly appreciated.

Please let me know if there's more information I need/should include.
Well, you've obviously got a misfire issue, and I don't think it is at all related to the head gasket.

When is the last time you put in a new distributor cap and rotor, new spark plugs (properly gapped), and spark plug wires?

That's where I would start first and foremost, especially if you don't know the last time it was done.
No problem. It could be the crank or camshaft position sensor as well, but usually those have more specific codes.

It also wouldn't hurt to pull out one of the spark plugs and see what it looks like.
Managed to replace the cap and rotor fairly quick and the plugs appeared to be in good shape. I'm still stumped at this point.
I forgot to note previously that my starter had literally fallen off a few nights ago, only to be bolted back on and working perfectly. It wasn't until after this I started experiencing problems with the misfire.
I think my next move might be to fuel. Will post back.
Thanks again for the help, Chris!
*edit- meant fuel, not ignition. LOL.
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Update :
Head is cracked (again),shop thinks the fan clutch /water pump might be the culprit. I found that cracks were pretty common in my TJ's engine, but is there something else that might be causing the head this much trouble?