Hey crew,

We have a 2001 XJ8 4.0l. Its running rough at idle and off the line, but straigtens right out with a little throttle. Its giving us cylinder misfire codes for all 4 cylinders on the right hand side. 1,2,3 & 4. What could be causing a misfire for the whole bank, and why would it smooth out with some throttle? Jaguars are new to us. Any help would be appreciated!

 

Broken Timing Chain?

 

Also had an emissions code, should have mentioned that.

 

pull the cam cover, one bank of misfires is a mistimed engine, when you consider the tensioners fail.