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2001 XJ Good ole heat soak problem


NAXJA Forum User
San Jose
Hi everyone,
After a couple of years of visiting this forum for tips and ideas, I've finally decided to make my first post regarding my 01 XJ.

A little backstory, I bought it off my dad's old mechanic who had got it off one of his customers and sold it to me. The jeep worked well for a couple of years until it started having some issues.
One summer on the way back from Tahoe , it started having the heat soak problem. I was able to drive it back home in San Jose. The issue seemed to go away for a couple of days until it came back and became more apparent.
Along the heat soak, it also threw the codes for multiple misfires ( Cylinders 3 and 6 -or maybe 5?) and the oxygen sensors. I tried the simple solutions first including the foil insulating sleeve but the problem didn't go away.

Not in the best financial place at that time, I decided to just tow the jeep to my parents' place to be parked and seen by the mechanic. Two mechanics have seen it and suggested to just replace the engine. While that may work, I don't think that's going to fix the issue long term. So I would like to ask for any recommendations or suggestions on any mechanics (hopefully and preferably around the Peninsula/SF/South Bay who may be able to for sure get rid of the problem and not just put a bandaid on it.
So owning an '00 when these heat soak and misfire threads pop up I read them.
Despite not having any issues.
I read the usual posts about spark plugs, fuel injectors, etc.
But sometime ago came across this:


Which led me to this:


Now I am going to be frank here but most of this goes over my head.
But it is not the usual rhetoric that you read when it comes to these issues.
Maybe it will be of use to you.
Exhaust leaks at manifold and at the precats. Tighten up those pre cats. Wrap injectors and fix exhaust leaks. Add
Hood vents.
I second the hood vent suggestion. I also have a 2001 and put on a set of LeBaron vents years ago. The amount of heat those things let out is incredible. It’s actually visible at a stop and you can see the shimmer as it escapes. Those engine bays are packed tight, with very little room for heat to escape.