My dad's 2010 X250 XF 3.0 TDV6 110k has started running rough, revs fluctuating at idle and getting the restricted performance message.

I've told him that reading the codes alone won't solve the problem, and they normally refer to an underlying cause. There's no smoke out the back.

I've said he ideally needs to get a garage to look at Live values for the turbo, intake, EGRs and DPF to narrow down the search.

However, the codes displayed are:

P0402(00) - EGR Excessive flow detected
P2263 - Turbo boost performance stuck
P0488(73) - EGR - throttle position control - range/performance problem


Thinking logically about this (it would be great for others to share views), my first port of call would be to look at the MAP sensor and see how gunked it is, to get an idea of any potential intake problem.

My next port of call would be to remove the hose and take a look at the throttle body. To me, it seems a stuck throttle body or one which has stripped its gears could cause all of the above symptoms.

Next would be to inspect the charge hoses, specifically the red one from the turbo, plus the actuator to see if it is seized.

Next, I would get a high pressure smoke test done, specifically looking for a cracked intake.

Finally, I would look at the EGRs. The L405 3.0 SDV6 is a very similar engine, so I'm hoping some forum members may be able to help. Having read up, EGRs aren't a known issue on these vehicles. I also wouldn't expect both EGRs to fail at once. 2015 Range Rover Autobiography 4.4 SDV8

Any details on the events immediately before?
A 100% guess would be charge air hose or manifold split, sometimes these come on suddenly with a bit of a pop, sometimes things just get worse over a period of time.
As you say, unlikely to be EGR - that'll be a symptom not a cause, the other two DTC's are linked, again, a guess - there may be an issue with the turbo actuator as the word 'stuck' doesn't usually feature with a charge air leak, it's usually a 'range/performance' DTC.