Besides a tired engine, and a decent 4.0 should last a lot more miles than 149k, is the torque converter locking and unlocking correctly? This and the power/comfort switch could greatly affect the feel.
I'd check the compression and verify timing just to have the basics done.
This is the third 88 xj that has recently been bought in this forum. Was there a clearance sale I missed ?
Although the two 88 motors were not the best. One has a stuck lifter and the motor is being swapped with a 95 4.0 they got for a song.
The other melted a piston and is being repaired, it also had a newer motor from a 93 xj instead of the 88.
(Im bad with remembering forum names, I believe 90xj06's got the 5 cyl xj, the Audi xj project?, BTW hows that going?)
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