My son bought a 83 xjs 12 cylinder it runs but just barely. if you flutter the pedal the rpms will increase. going up a hill you have to flutter the pedal to get it to pick up speed. it backfires until it's warmed up, and even then it does occasionally. we put a new distributor cap on it, but were unable to get the rotor out. is there a trick to it? any help would be appreciated. any pics and/or descriptions would be helpful, we know nothing about a 12 cylinder engine.

 

Did the car sit unused for a long period?

If so, pull the fuel filter and empty the contents into a clean container and post back with findings

Cheers
DD

 

Welcome aboard mrtransams, I see that you are already in good hands.

 

Fule filter is fine in did sit for 8 or 9 years runs but backfires and no power wont pull it self up a small hill