Edited on 2006-09-05 10:06:03

Edited on 2006-09-05 9:52:52

I am a VW mech. by trade but always had a soft spot for jags.
I picked up an 84 XJ12 VDP which has a few issues and slowly sorting them out, but not familiar with jags, I am currently looking for some manuals, but in the meantime I have a few issues I could use help with, the car hesitates and bogs while accelerating if I let off or give it more throttle it smoothens out and works fine, once fully warmed up the problem goes away. The other is clunks in the front end whenever I hit a bump.
I have checked the front over, ball joints, tie rods etc. bushings all look fine. The clunks are coming from either side of the car, depending on which side hits a bump of course.

I got the car for a very reasonable price, the owner was told it needed a new steering rack and they were tired of spending money on the car. I dropped the rack and replaced the small steel pressure lines and now it is fine. The rack bushings are fine also.

Also wondering if body panels are the same between the xj6 and the xj12? mainly the front fenders, they look to be the same to me.
Any suggestions? Any help would be appreciated.....

Submitted by dougdwyer@adel… on Tue, 09/05/2006 - 22:15

Clunk: after checking the shocks go to the diagonal braces that run from the firewall to the fenders. Make sure they are tight. Really tight.

Hesistation: my first thought is the throttle position sensor, a fairly common problem. Backprobe the yellow and red wires (green is your 5v reference)and look for a steady smooth voltage increase as you open the throttle. At idle you should have +/- .32v and a WOT throttle about 4.8v or so.

Also check you dist advance. It is very common for the vacuum advance diaphram to be toast, and the mechanical advance mechanism inside the distributor to be seized up.

Fenders: The exterior sheet metal is the same XJ6 vs. XJ12

Doug Dwyer
Longview Washington USA
1995 XJR
1988 XJS

Submitted by bcantrel@clarian.org on Tue, 09/05/2006 - 12:12

I have an 80 and an 84 XJ6. I had the same issue with both and it was the rubber bushing at the top of the shock absorbers where they mount to the top of the fenders. I bought a universal kit for a local auto part store and it was all fixed in about 15 minutes.

As far as the hesitation and body panels, I'll leave that one to the experts.