I have a 2011 XF 5.0, that we recently picked up cheap at auction. It’s in immaculate shape and only has 97k miles. I threw in new cam sensors all around. However it runs like ****. There was no exhaust pressure from the passenger side, so I pulled the cat thinking it was clogged. However after firing it up, there’s almost no exhaust flow from the header. Only the occasional massive fire ball every 10-15 seconds.


I’m really hoping it’s not something as drastic as the timing chain guides. But I really can’t think of anything else that would kill an entire bank of cylinders. Any ideas?

 

Can't help with your problem but the pictured car is an XJ not an XF!

 

Couple of things that come immediately to mind as feeding one bank: Injector harness, Coil-on-plug harness.