2000 4.0 fault cycles
 

When the check engine light comes on and codes #3 cylinder misfire and #4 cylinder misfire are displayed on the obd II indicating a cracked head. After resetting the check engine light how long before the check engine light would come on indicating the same codes on a situation with a cracked head?

The cell would come back on almost immediately or after a few times cranking it over , if you do end up with the cracks head I heard Clearwater is the best for your buck and it bolt right on. Good luck with everything l.

I bought the xj 157000 miles as is Christmas Eve.. When I test drove it there was no light. When I picked it up from the lot the check engine light was gone and so was the dealer. I called them to let them that the light was on and blah blah blah on Monday. Since then I had plenty of homework to do that I should of done prior. The head was.cracked. today I went and showed my obdII readout to the dealer along with some pictures of the valve cover cover removed and they refunded my money and all's good.

Thanks for replying. I thought I smelled a rat so I was preparing.

Time to start shopping for another jeep with a 4.0