I just purchased a 95 XJS convertible, and it idles rather fast, about 1200
RPM.  It's not throwing any codes (no "Service Engine" lights are on) which
I would expect if it was a bad idle control valve.
The valve are rather pricey, is there some simple test I can do to verify

My 1988 XJS V12 has decided to shed all it's engine oil over the road via
the oil cooler. (I noticed in time by seeing the black line out the rear
view mirror, Yes, that bad!) Do I really need the oil cooler, If not, what's
the easiest way to bypass it?

I have a problem with my 1997 XJ6 that has me stumped. The engine will
momentarily cut out from bumps and potholes in the road. Occasionally the
engine will actually die (restarts easily) but most times it just cuts out
(RPMs drop off) and then continue running. The check engine ...

1995 XJS, I noticed the bulb failure light comes on when I brake.  Both
brake lights have failed, but the high mounted light is working.  Both
bulbs are good, and the fuse for the brake light circuit is good.  Any
ideas?

  Is there really any difference in the fluids and filters that are offered
through "Jag approved" and aftermarket parts? I was told that Jags have a
weaker oil pump than American made cars and require a thinner paper filter
though Fram offers a filter for less and Prestone ...