Hi Looking for some advice/opinions
I have a 2013 L405 4.4SDV8. I understand the turbos are sequential with right hand one operating and normal driving and is a variable vane turbo, the left hand is a standard turbo and only kicks in at approx 2800RPM
When Im driving it performs normally but if i really accelerate hard and under load and take revs above 300RPM my car goes into restrictive mode. Does anybody have any ideas why that is. I have been advised that right hand turbo veins are "sticking" but what i dont understand is this only happens above 300RPM

For a laugh, buy a can or two of Sea Foam, or similar, follow instructions and see what happens. It might save you hundreds, you never know.

https://www.amazon.co.uk/Sea-Foam-Motor-Tu...B07KRLT3T5 L405 P400e Autobiography (MY2020)... Silicon Silver / Espresso

Interrogate for fault codes. That will point you in the right direction

Check that the CSOV air change over valve is moving freely and not stuck.
Bulletin in Wiki.

Mike.
http://www.fullfatrr.com/gallery/albums/us..._TOPIx.pdf G reg 2.5VM Vogue Portofino red 1991- 1999
V reg 2.5td P38 Rioja red 1999- 2006
53 reg td6 Vogue Oslo blue 2006- 2015
11 reg 4.4 TdV8 Vogue SE. Baltic blue 2015- date.
https://www.fullfatrr.com/forum/topic56162...tty+affair

I would put money on it being a boost leak.
we see a lot of these on 4.4TDV8 L322's but less on the 405

that's because part were revised however yours being a 2013 I'd be checking the donut hoses and the throttle body joint .

CSOV sticking is also a possibility.

None of the above are difficult fixes

Good luck
. Cheers, Greg
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
2011 Vogue SE 4.4 with lots of toys in Stornaway

Hi Thanks for that will look into it

Carefully check the seams around the plenum donought with a piece of tissue/ kitchen roll looking for sooty black oily tell tale signs of a leak.