Haven’t tested compression after the valve job since it’s running normal again but I’ll throw the tester on there when I get a chance. I believe 80psi running compression is pretty normal for a 4.0 with 225,000. We have another xj with 230,000 and it has about 80psi for running compression too...
I searched high and low on the web while trying to sort this issue so I figure I'll share and hopefully save someone else some time.
A few months ago my 1996 xj 4.0 aw4 started having a rough idle and p0300, p0301 codes. Other than that seemed to run fine. I tested/cleaned injectors, tested...