my xj jeep when cold will skip and jump when the foot is on the acclerator.

Australia
December 5, 2006 11:30pm CST
when i start up the xj jeep 4lt. it starts fine. then when its in park i try to rev the engine and it will jump and wont rev properly. then engine just wont hold the rev's like when taking off it will just kind of die then pick up again as i hold my foot on the gas . the engine light comes on and has stalled sometimes When the car is in drive it does the same thing,, its like it wont hold a gear but i know its not the auto gear box because i had it changed over to a 2nd hand one. this problem is very bad when cold but when the car is a running temperature it seems to be 100% normal with no problem at all. i had the car scanned but they found no problem. can anyone please help. regards, justin
1 response
• United States
6 Dec 06
If the check engine light comes on there is a code stored in the jeeps computer. It could possibly be the oxygen sensor. It may need the fuel injection system professionaly cleaned also. What year is the jeep? This comes from my bf who is a professional mechanic, and just worked on his ex's jeep.
• Australia
6 Dec 06
thank you for the reply. its an 94 xj auto. the plug on the side of the engine from the oxygen sensor is dirty from a few dirty mud holes and i found out that the sensor has not been replaced in the last 5 years or more. thank you for your help. I am in australia by the way and my xj is right hand drive but it still is the same in every respect. thanks