I have a 2005 XJ6 and the engine malfunction light came on a few months ago and then went away. It came on flashing the other day and seemed to lose power for a while then was ok and light went out. Then about 50kms down the road it did it again. I have put a scanner on it and it comes up with P0171 code . Bank 1. I have changed the fuel filter. But it has a noise in the front end when it is idling but not while driving. Can anybody help me. Thanks Barb

 

Flashing = severe misfires, causing cat conv damage. Do not keep doing that!

Go air leak hunting - see the many threads about your code.

 

Try to investigate the noise when idling since it could be related to the air leak. eg loose or broken hose.

 

Thanks mate. Have now taken it to a Jaguar Specialist in Perth. hopefully they will fix the problem without me doing a seek and trial and error. Cheers Barb