Charge pressure control positive deviation, N75??

[Jay111s]

New to this forum but any help would be appreciated. I've an Audi A3 tdi 130, fairly high mileage 160k, last week as I pulled away on the motorway at around 60-65mph it went into limp mode, it had never done this before then on the return journey initially driving around the town ok but again as soon as I pulled away on the motorway around 60-65mph it went in to limp mode.
I've ran the VCDS lite and it returned error code 17965 Charge pressure control: positive deviation, P1557 - 35 - 10 -- Intermittent.

I've read various website about replacing the turbo or N75 sensor, any suggestions where to begin??

 

[badger5]

sticking vnt?

 

[JimS3]

The n75 is a control valve not a sensor found on the petrol cars.

The 130 tdi has a similar vacuum valve, it is attached to the bulk head, it's the one with the white top.
The black top one is the N18 that operates the EGR.

Check the vacuum hose from the valve to the turbo, and the whole vacuum system for splits.

if that does not solve it it's likely the variable vane mechanism in your turbo is stuck. Search on google for the mr muscle fix.

 

[Jay111s]

Thanks for your help. The hoses all appear to be intact so I'll give it a go with the Mr Muscle this week.

Anyone else done this on an A3 tdi 130? any advice / photos appreciated.

 

[JimS3]

Thanks for your help. The hoses all appear to be intact so I'll give it a go with the Mr Muscle this week.

Anyone else done this on an A3 tdi 130? any advice / photos appreciated.

Long gloves are a must, first time I used it I had painful burns from the oven cleaner that lasted a couple of weeks.

Will help if you get a pair of mole grips on the VNT rod and work it back an fourth while spraying the cleaner in.

And while I'm sure this is obvious, it's the down pipe you need to remove and spray it in the hot side.
Only state the obvious as it's surprising the number of people I have seen spray it in the cold side and wonder why it does nothing!