Hello everyone,
I've been having troubles with my 1996 DD6 (6.0 V12). It started to shake in idle (only very slightly though, but still noticeable in comparison to the way it should be) and consuming more fuel. I checked the fault codes and it showed P0307 (Misfire cylinder 7) and P1314 (Misfire - Catalyst Damage). Cylinder 7 is the frontmost cylinder on the left bank, right? I checked compression on that cylinder which is the same as on the other cylinders. Spark is also there and easily visible and audible. High tension wire has correct resistance. I think the misfires don't occur permanently, though as when I last drove it, I could suddenly feel a reduction of power which disappeared again. Is it recommended to change the coils and high tension wires and see if the problem disappears? Any other ideas? I also thought of replacing the fuel injector.

My second problem is an irregular knocking noise, similar to an electric fuel pump. It occurs at idle and is only audible from inside the car. It doesn't come from the engine. As far as I can located it, it seems like it comes from behind the dashboard or the front floor. Is it a known problem?

Thanks for your help,
Valentin

 

You may find help here, but you will be more likely to get a response posting on the X305 forum, which covers your V-12

XJ ( X305 ) XJ12 - Jaguar Forums - Jaguar Enthusiasts Forum

 

Thank you, I posted it there now.