XJ Cherokee 4.0 Litre Engine Hesitation / Misfiring

[HeroHari]

Hi all,

I bought a 2000 XJ Cherokee Orvis (UK) 4.0 litre auto last week with 150,000 on the clock.
Excellent service history and in good condition.

However, I've been driving it for short distances (6 miles every other day) and I've found that it has a engine hesitation / misfire issue (I'm not sure what the difference is between a hesitation and misfire so I've referenced both).

For example, this morning on the way to work it actually stalled for the first time. And when stationary in traffic I could tell that the engine was struggling against stalling and when I put my foot on the accelerator the revs would occasionally die but if I put my foot down the car would come back to life again.

It wasn't that bad on the way home from work and I've just been out in it tonight and it was ok.

I did notice that on the service history this issue started at 128,000 and the owner was quoted for a new engine ecu and 2x lambda sensors (by a none Jeep garage), but I've got no record of these being fitted.

The misfiring issue emerged again at 140,000 on the service history and a new plug lead set was fitted and the spark plugs were cleaned.
The spark plugs were cleaned again at 149,000.

The car hasn't failed on me...yet...so if it's just an annoyance I guess I could put up with it as I really don't want to spend anymore money on it at the moment.

Also, I've run the self diagnostics test using the trip switch on off x3 times method.
And NO codes were displayed.

Any advice would be most appreciated.
Please note that I don't know anything about the mechanics of cars when you reply :-)

Many thanks

[Mudderoy]

Hi all,

I bought a 2000 XJ Cherokee Orvis (UK) 4.0 litre auto last week with 150,000 on the clock.
Excellent service history and in good condition.

However, I've been driving it for short distances (6 miles every other day) and I've found that it has a engine hesitation / misfire issue (I'm not sure what the difference is between a hesitation and misfire so I've referenced both).

For example, this morning on the way to work it actually stalled for the first time. And when stationary in traffic I could tell that the engine was struggling against stalling and when I put my foot on the accelerator the revs would occasionally die but if I put my foot down the car would come back to life again.

It wasn't that bad on the way home from work and I've just been out in it tonight and it was ok.

I did notice that on the service history this issue started at 128,000 and the owner was quoted for a new engine ecu and 2x lambda sensors (by a none Jeep garage), but I've got no record of these being fitted.

The misfiring issue emerged again at 140,000 on the service history and a new plug lead set was fitted and the spark plugs were cleaned.
The spark plugs were cleaned again at 149,000.

The car hasn't failed on me...yet...so if it's just an annoyance I guess I could put up with it as I really don't want to spend anymore money on it at the moment.

Also, I've run the self diagnostics test using the trip switch on off x3 times method.
And NO codes were displayed.

Any advice would be most appreciated.
Please note that I don't know anything about the mechanics of cars when you reply :-)

Many thanks

Hmmm i wonder if this is heat soak issue. Guys?

[cantab27]

tps??? is it shifting ok..... welcome to the site by the way.......

[4.3LXJ]

Misfiring at idle or at higher rpms? When cold or warmws up?

[HeroHari]

Hi, I took it out for a brief run around a quiet site and it was a warm day in the UK today and I didn't have any issues whatsoever.

The Jeep drove perfectly!!!

So, I can only compare this with the other mornings which have been cold.
Could this be the issue then that it's only happening on cold mornings?

What could that point to?
Thanks

[4.3LXJ]

I don' know yet. I am leaning toward a sticky idle air controller unless I get more imformation.

[pvt.tadpolxj]

Most of the time these thing's are minor.:pray:

[LizardRunner]

first thing I would check is the idle air controler, then I would check the CPS then the TPS. Mine would do stuff like that when I first got it and as I went through the list it became apparent it was a Crank Position Sensor propblem, second time through the list. Replacing that has led to bigger smiles as I put on the miles :D

[grimhelm]

I have a 2000 Cherokee also. I had a problem with hesitation also. I kept having different codes pop up first misfire, replaced the coil. Then the camposition sensor, replaced it. Then the crank position sensor, replaced it. Then the same codes started poping up again. I pulled the distributor or on the 2000-2001 Cherokees oil pump drive. The top bearing was starting to seize up. I replaced it with a used one. I had no more problems for about 1&1/2 years, then the used distributor started doing the same hesitation. About 20 more miles and the distributor seized up stopping the motor. The motor wouldn't crank over either. I was out of town and none of the auto parts stores can get it. It's not even listed. I pulled it apart and the same problem as the last one. The oil that keeps the bottom bearing lubed doesn't get to the top bearing. I smoothed out the shaft and bearing the best I could being out of town and lube it with wheel bearing grease. This got me back home. On further investigation back home, the dealership was the only one that had a replacement $320. To steep for me, called up a Jeep salvage yard. They sent me one for $60 including shipping. I was going to have the same problem in another 1&1/2 years if I didn't do something different. If the top bearing wasn't getting lube, then I would get it there myself. I drilled a hole in between the two bearings and put a zerx fitting in it. Not wanting the grease to get into the oil, I sealed the weep hole in the bottom of the shaft that lets the oil in and gets to the bottom bearing. About every six months I pull the distributor and give it a couple of squirts of grease. I usually have to turn the oil pump drive counter clockwise a little bit with a long screwdriver to drop the distributor back into place in the exact same position, not effecting the timing. It's simple enough to do and has solved the problem so far, 2 years. Don't know if this will help you but it might not hurt to pull the distributor and spin it. If it is hard to turn it might be the same problem.