i just got my first jag a 88 xjs and it was idleing at 1600-2000
i traced the issue to a stuck aux air valve
so i am in the process of rebuilding it
i cleaned and oiled everything properly but the instructions i found are poor at best
they stated that the therm bulb is a seperate piece but no mention of the outer disk holding it in place i somehow broke the seal that keeps the bulb from spinning within the outer ring
the bulb itself is not damaged in anyway other then it needs resealed
if anyone knows of a good high temp adhesive please let me know
i was gonna use jb weld but i dont really know if it would work and i dont want that stuff floating around in the antifreeze and i deffinantly dont want antifreeze getting sucked up into the vac system

 

kinda strange replying to my own post but...
after asking around i gave jb weld a shot and it is working fine
i am gonna buy a new valve, just needed to buy some time
just wanted to reply on the off chance someone else had the same problem