Hey I'm new here and I have a bad problem with my xj. Recently it has been idling kind of rough especially in reverse and drive. When I'm driving it starts out in 1st kind of rough but by the time it hits overdrive the whole jeep is shaking really badly. I do believe that it is skipping but I don't know why. I've checked the spark plugs and wires and I've blown out some of the vacuum lines that had a decent amount of oil in them. What is causing this?? Please Help!!! Its my DD, it has a 4.0L automatic.


Oh and I'm not sure if this has anything to do with it but I just fixed an oil leak at the filler cap, so maybe its blowing more oil in the air box which in return puts more oil build up in the vacuum lines going out of it??? Not sure... Thanks if you can help!!!!

 

I know there are a lot of posts on here and I've read them all, but nobody says what they found the problem to be and answers are being thrown everywhere... forgot to throw that in

 

When mine did that it was the 02 sensor. No codes either.

 

How did you "check" the wires?

Did you look at the cap and rotor?

What was the plug gap?

 

Is there a way to test the O2 sensor??

 

Well we made sure that the wires were not crossing or arcing. And we did not check the cap, should we?? It didn't seem that big of a deal. We didn't look for a plug gap, we just made sure they were clean.

 

With the proper diagnostic equipment, the O2 sensor(s) can be observed in action.

But, you're blowing oil out, can't tell us what the plug gap was or how you "checked" the wires. Haven't told us what the cap and rotor look like...

Maybe you should take it to a shop?

 

We posted at the same time.

Heck ya, it's important.

The plugs, wires, cap and rotor are due to be replaced every 30,000 miles.

Have you read the link in my signature below?

 

Okay today I had my uncle come down to take a look at it and we rechecked the wires again and one of the wires were sparking orange instead of blue. So this weekend we are replacing the wires, plugs, distributor cap, and the rotor button. Since these were already faulty might as well replace them.

 

Nope haven't read it but I will try to when I'm able to. And I really didn't think to measure spark plug gap....

 

I like your uncle even though I've never met him.......