I recently purchased an 85 XJS from a friend of mine and it doesn't want to stay running. It needs a tune up, so I'm hoping it's just due to running a little rich or maybe incomplete combustion that's the problem but this is my first Jag and I'm not familiar with it it all. It'll fire up and idle just fine, but when I put it in gear or even blip the throttle sometimes it seems to choke on the fuel and slowly quit. I'm getting new plugs, wires and replacing the cap and rotor as well and I'll see where that gets me. Any input from someone withany experience would be much appreciated as I can't wait to drive this thing!

 

anyone?

 

thanks for nothing everybody, can't see why 43 views and no one had a helpful word to say...anyway, hopefully this can help someone with a similar, or no-start problem. there is a sock type filter in the surge tank that had become clogged with the various particulate in the tank from the previous owner letting the tank get extremely low. i couldn't find a replacement without waiting two weeks to get it so i used some fine wire mesh and a hose clamp as a temporary issue. fired with up and ran great.

 

seems to be a very common issue, this was suggested by a member on the jag-lovers.com forum, my original suspicion was confirmed after a chat with the dealer and a local jaguar specialist

 

JBurdon: had the same problem years ago on an XJ-S. I removed the little sump tank, and cleaned it and the filter at the same time. THEN I installed a filter between the main fuel tank and that. I never could understand Jag having a fuel filter after the fuel pump.
I would have responded earlier, but this is the 1st time I have seen this post.
If you would like to see what a proper XJ-S V12 can do, Google my name:Chadbourn Bolles
Check the 3rd video down, if you have hi speed internet service, if not, don't, it is 11 min long.
I was going to send you a pic of my new engine, but do not know how to attach a pic here.
Dr.Chadbourn Bolles
803 532 6257

 

J. Burdon is correct; that is a common problem. I have that cleaningtask on my spring time to-do list.

I just registered here so I could not reply before - I just read this thread for the first time.

 

JBurdon, First of all, don't be rude! WFT, you come here to ask for help and become an A-hole? Second of all, why are you throwing parts at the car if you don't know what the deal with it is anyway? Spark plugs, wires? Is the car starting up? Then there is spark, why you need wires? Do you have fuel pressure? Is it within norm? Is ignition TIMING correct? Get your facts straight, before you come here and scald people.

 

V12 will die if rpm drops below 500rpm, this may be why it idles fine, but stalls in gear. Raise the idle speed in gear >500rpm.