XJ problem

[East-Gippsland-XJCherokee]

Hi all,

Joined today as I was looking for anwers to try and sort out my XJ and found this great forum!

I had just replaced a broken harmonic balancer on my 1996 XJ Cherokee 4ltr auto and this problem started. My XJ starts perfect every time, runs absolutely great, great power and smooth, I get down the road lets say 5 miles or so and when the car is at about operating temperature it starts to hesitate badly, its like I am hitting a rev limiter at around 3000RMP, if I put it in neutral and turn the engine off then restart it tends to clear it for a very short while and then starts again. As soon as it cools down a small amount it seems OK until operating temp is reached again. Can anyone help?

Plugs/leads/rotor cap/clutch fan/waterpump are about 1 year old, and my XJ is always serviced. It runs a large Adrad radiator, extractors. All I replaced was the harmonic balancer as the out ring came off, replaced it and 2 days later this problem started. It does not overheat and runs perfect until it gets to operating temp, my suspicion is the Air Temp Sensor due to this problem happening when it is at operating temp.

Seeing I live fairly remotely I am trying to pin point what the cause is before I order a bunch of sensors/parts via Ebay.

I did find a very similar if not the same problem on a US forum but there was no clear outcome or solution please see link. http://www.jeepforum.com/forum/f13/1...thing-1260551/

Any help advice would be greatly appreciated, as I would hate to try my luck with the local mechanic in town that seems good at servicing standard cars, but paying for some one to change 1 sensor after another is something we all can do with paying for the labour.

Cheers guys.

[anthonygubbin]

It's sounding like a sensor. The go is to have it scanned at Super Cheap Auto if you don't have your own scanner. A scan is about $25 at SCA.


Regards A

[East-Gippsland-XJCherokee]

Originally Posted by anthonygubbin

It's sounding like a sensor. The go is to have it scanned at Super Cheap Auto if you don't have your own scanner. A scan is about $25 at SCA.


Regards A

Thanks Anthony,

I was not aware they provide that service, easy enough for me to drive into town on my next supply trip, I will ring them before hand to see if they are aware of it as well.

[junglejuice]

First of all welcome...

Normally issues related to temp usually involve one of the two CPS units (Crank and Cam Position Sensors), the Cam sensor is in the dissy, the Crank sensor is on the passenger side bellhousing.

Be aware that having a 96 model (of which were all 4L auto in Oz) that there was a change of sensors in that year, some use the older OBD1 sensors and the the others use the newer OBD2 sensors, if you want to know which yours uses take a close up pic of the temp sensor in the thermostat housing and post it up and I can tell you which variant you have.

To quickly check if it is the Crank sensor (most common failure) pour cool water over the ensor when it plays up and see if it changes at all.

Other common temp issues involve the coil....

Be aware that Xj's can be sensitive regarding battery condition and can very much affect the way the car runs....

[East-Gippsland-XJCherokee]

Originally Posted by junglejuice

First of all welcome...

Normally issues related to temp usually involve one of the two CPS units (Crank and Cam Position Sensors), the Cam sensor is in the dissy, the Crank sensor is on the passenger side bellhousing.

Be aware that having a 96 model (of which were all 4L auto in Oz) that there was a change of sensors in that year, some use the older OBD1 sensors and the the others use the newer OBD2 sensors, if you want to know which yours uses take a close up pic of the temp sensor in the thermostat housing and post it up and I can tell you which variant you have.

To quickly check if it is the Crank sensor (most common failure) pour cool water over the ensor when it plays up and see if it changes at all.

Other common temp issues involve the coil....

Be aware that Xj's can be sensitive regarding battery condition and can very much affect the way the car runs....

Hey thx for the welcome JJ!

When it hits that mysterious induced rev limiter, I keep telling myself it is ignition related, just feels like problems I had with my V8's when I was younger, although those cars did not know what an ECU was. The battery is in near perfect new condition, and seeing I can get a scan done (hopefully in town) I will start there, but no warning light has come on of any kind.

I will keep you posted if it gets to thepoint of taking a photo to show you, and yeah guys I really apreaciate the advice and help!

Cheers, beers all around when the beast is running good again

[East-Gippsland-XJCherokee]

Originally Posted by anthonygubbin

It's sounding like a sensor. The go is to have it scanned at Super Cheap Auto if you don't have your own scanner. A scan is about $25 at SCA.


Regards A

I checked online and the nearest SCA is about 500k's away, looks like that plan is not going to work.

[anthonygubbin]

Ebay has scan tools for around 80-90 bucks. If you have a smart phone you can get some that work with an App and they are around 20-30 bucks. Only thing is they don't always throw a code, which may be why you don't have a CEL.

Regards A