XJ's 4.0L Hit an all time low.

[Osprey413]

Well im still not sure what the electrical problem is. I went out and wiggled every wire i could get my hands on and still no miss. But, I think I may have found where the oil leak is. I think it is coming from the fitting the oil filter goes on. Not around the oil filter itself, but where that fitting meets the block. I don't know if this is good news or bad news because I don't have much experience when it comes to the internals of engines. Any thoughts on how bad of a fix this will be?

 

[jldiaz]

Good news: It's probably just the O-ring.

 

[Osprey413]

Is it common for those to go bad? The Jeep has about 113000 miles on it.

 

[jldiaz]

Not really. Probably a bit early, but not uncommon.

 

[Mercenary]

Those O-rings are super easy to replace. I just did mine on my 92. Bought the kit from the dealer and took me about an hour of farting around with other stuff to fix it.

Cant help with the electrics tho

 

[woody]

1st off, fix the electrical glitch... I second (or third) CLEANING the grounds with 80 grit sandpaper and smearing a dab of GB Oxgard on the connections. Since you have not finished the tune up, grab a cap & rotor and sling em on there (2 screws @ 5 minutes) Shoot a dab of dielectric grease into the plug & coil wires too.

The oil filter adapter o-rings are easy...there is a large one where the adapter meets the block and a smaller one at the bolt head. I am unclear how your filter sits: on my older non HOs, the filter sits upside down, and the adapter must come off to change the motor mount on that side. 113,000 & 7 years old? I'd wait till it's time to change the oil, then before ya fill it back up, replace the mounts, those o-rings, a new filter, and oil. :dunno:

 

[PlainWhiteXJ]

you did a tuneup and did not change the cap and rotor ? Just the plugs and wires ? The cap and rotor also wear out. Maybe it's just me but I consider all those parts as wear items and generally replace them yearly at the same time.
Before I started throwing a bunch of stuff at it I would go back to STOCK OEM DEALER SUPPLIED plugs, wires, cap and rotor. Then I would see what I have from there.

RichP - why the fascination with very particular brands of ingintion parts (you like OEM, I thought I read some threads where people liked other stuff.) Does it really make a difference with Jeeps? I'm relatively new to the Jeep world, but never seen people care this much about brand with other cars and trucks (as long as you stay away from junk).

 

[lawdog]

It may be a long shot but have you replaced your fuel filter. Although it was constant, My cherokee had a bad sputtering problem that was cleared up when I replaced the fuel filter. Also check every electrical connection you can find. Mabey one of the injector connections came loose when you were replacing the spark plugs. It's usually the stupid little stuff that gives you the most problems. Good luck

 

[Osprey413]

Well, my Jeep is in the shop now. I got closer to finding the electrical problem, but I still couldn't pinpoint it. I found one wiring harness that ran along the firewall behind the rocker cover that when I wiggled it the Jeep would miss, but beyond that I couldn't find the problem. I wiggled every connector and wire that ran through that harness but I still couldn't get it to miss. So basically I gave up and took it to the shop.
The oil problem has magically dissapeared. It leaked that one time, and hasent leaked at all sense. I drove the Jeep back home, which is a 2 hour drive, and not a drop of oil leaked. I think the oil leak only occurs when I stress the engine to the max (the oil leak occured before when I was driving way too fast down the highway in third gear so my RPM's were staying at about 4500 for an extended period of time). I'm not really worried about the oil problem anymore, I just want this damn miss to go away.

 

[witt]

dood...
4500 rpm for an EXTENDED period of time.... no wonder your 4.0 doesnt like you
the 4.0 doesnt like to be spun @ high rpm's for very long....