First all I want to say Hello, Im new to the forum but a long time Jeep guy.

Earlier this year I purchased a 99 XJ with 78K miles on it. Super clean interior and a little bit of paint bubbling on the rockers, other than that a super clean ride.

About a week ago i started having problems with stalling and rough idle. And about a month before that it seems to take a bit longer to start, not all of the time but most.

At idle it almost dies, rpms drop to 500 or so and it corrects itself and ramps up than back down. If i drive it will stall a few times before coming out of it and runs fine after that.

I have checked for vacuum leaks and found none so far. Not sure what is going on.

Im hoping someone can help.

Thanks

 

A good cleaning of the throttle body and the problem is fixed.

 

Nice work!

 

It's seems to have been the upper O2 sensor.