my jaguar 2002 xtype 3.0v6 runs ok but will not rev over 3000rpm and is showing p0171 fault.i now this can a number of things butwhere do i start?

 

Welcome to the forums. You have come to the right place. This is most likley caused by a vacuum leak and that is putting the car into limp mode. The three most common areas to look at are the IMT O-rings, the brake booster check valve and the PCV hose. There is a ton of information on here about that. Do some searching on here for that code and you will find all the info you need. Those issues are very simple, easy and cheap to address. Good luck.

 

 

thanx for all info think my mechanic now knows where to start.