I've been having an issue with my 2011 3.0 diesel XJ. Restricted proformance.
The MAF sensor for the right side of the engine is reading low but when I swap them around it still reads low. So I put my hand over the intake for the left side and it's drawing air but the right side is not. All pipe work is connected and looks good. So I suspect the turbo is faulty.

If anyone has seen this issue is it's not the turbo can you let me know.

 

I hope you know how bi-turbo system work on 3.0D engine? Only one turbo operate on low rpm. 2nd turbo join on party around 2800-3400rpm depending confitions. -> If you read airflow from MAF:s when engine is in single turbo mode, you had correct readings.
What are the actual fault code caused restricted performance?

 

No I didn't know that. So how do I take the correct reading.do I take a test drive and read off the live data
The fault comes into the car at about 70mph the engine is at about 1400 rpm.

 

"Air flow too high" code for sure indicates an leak on intake piping on pressure side of the intake (after turbos).
I would focus on:
- Throttle housing and joint+pipe before it (top front of the engine)
- Intercooler (bit hard to accees)
- Intake manifolds (seek oily areas on top of either banks, you might need to peek under noise insulator paddings)

An smoke test is good way to find leaks.

 

Adding for above: Its possible that you might have stuck turbocharger bypass valve as well. (located low front of the engine)

 

Thanks for all these pointers. A do see some fresh oil splatter on top of the engine around the throttle body. This all started after my NCT test (MOT test). Bypass valve looks like it's working good. I'll look into it and get back to you.
Thanks again.

 

Vasara. You were right. I checked the area around the manifold and boost pipes and found oil on the throttle body. When I put pressure on the back of it I could see some movement. So I didn't even have to go find someone with a smoke machine.
I went to fit the new throttle body and the whole back section broke off with no pressure at all. The new one in fitted and the problem is gone.
Thanks for all your help. You saved me time and money.

 

Hi 11XJ
Great to hear you got it sorted and thanks you reported it here.