transmission??? PLEASE HELP

well my brother has a 00 jeep cherokee and i dont know if its his transmission or not but when he starts his car when the motor is cold it will take off just fine and shift fine (its an automatic)but when the motor begins to start warming up, when u try to take off it just takes off very very slowly and then a few seconds later it just kicks in hard and takes off like normal......it only happens when u make a complete or almost complete stop and have to take off again, .........his check engine light is on...so any help would be great..........also we put new spark plugs in, air and oil filter, and new tranny fluid.......and it still does it, ( and one more thing...i own a honda and i know when my check engine comes on i can just go to my ecu and check to see what code its throwing and just fix the problem...do jeeps have that??? so i can check that if it does) sorry for it being soo long....but thanks for all the help in advance...u guys always seem to be very very helpful.....thanks again....l

You should be able to have the codes pulled at you local parts store. There appears to be several AutoZone stores in your area. They will usually read the codes for you or lend you the tool to do it.

That would be step 1 to see what is going on.

Take Care,

do they charge anything to pull the code???

I agree with GregA; AutoZone will do the service free of charge. The tranny is computer controlled.

Fluid level: is it at the proper level? The engine and tranny *must* be at normal operating temps (about 30-45 minutes of around town stop and go driving will get everything up to temp....not a 10 minute blast on the freeway) and the engine idling and in neutral. An overfill is generally worse than an underfill but either situation needs to be rectified. Too much fluid can result in aeration (foaming) of the fluid and this will cause a loss of hydraulic pressure (which is how the tranny works)... and in the end possibly cause the trans to slip....Possible scenario: cold start, the fluid is solid (not aerated); as the engine/trans warms, the fluid expands and, due to overfill condition, begins to aerate causing loss of system hydraulic pressure.

Good luck and tellus what happens....

mike
00XJ

well my brother has a 00 jeep cherokee and i dont know if its his transmission or not but when he starts his car when the motor is cold it will take off just fine and shift fine (its an automatic)but when the motor begins to start warming up, when u try to take off it just takes off very very slowly and then a few seconds later it just kicks in hard and takes off like normal......it only happens when u make a complete or almost complete stop and have to take off again, .........his check engine light is on...so any help would be great..........also we put new spark plugs in, air and oil filter, and new tranny fluid.......and it still does it, ( and one more thing...i own a honda and i know when my check engine comes on i can just go to my ecu and check to see what code its throwing and just fix the problem...do jeeps have that??? so i can check that if it does) sorry for it being soo long....but thanks for all the help in advance...u guys always seem to be very very helpful.....thanks again....l

Auto Zone or Advance will pull the code for free.
As for you trans prob, since it is electronic you should check the MAP sensor and vacuum line. If there is a hole in the line or the sensor is going bad it will cause the conditions you are talking about. The procedure for testing the MAP sensor is in the HAYNES repair manual.

sector95 and wwwildman thanks for breaking it down for me i will for sure let u know what happens....and u too GregA....but where would be the best place to get a haynes manual??????...i know theres a website but u cant look at how to repair it from the web page u have to buy it right????thanks again for all the help

If you're even half-way serious about wrenching on your XJ, then get a real Chrysler Factory Service Manual (aka: FSM). The Haynes/Chiltons can get too generic and in some cases not cover certain systems. Go on line in a Google search for "jeep factory service manuals" or check on eBay. I bought a manual on eBay (and one on CD) for my '00XJ and they are way better than any store bought book. You should be able to find one for about the same price or a little more than a Haynes/Chiltons book.

Happy hunting...

mike
00XJ

Sector 95 is correct about the Facotry service manual, it is better that the rest. The haynes manual does a pretty good job but is not as detailed as the service manual. Auto zone or advanced should have the Haynes manual.

well my brother took his car into autozone and they said its something with the transmission.....idk....i probably will take it in myself and see whats up and pick up a manual while im there....i will let u guys know what happens from there.......later, thanks