Lately my 2001 (130hp) passat has been going into limp mode and shutting the turbo down. No engine management lights are coming on. It has 182k miles on the clock.

I took it into vw who carried out a 'guided fault finding and diagnostic test plan' and concluded the turbo was faulty. The also noted faults were being stored, but didnt confirm what. They quoted a huge £1300 to replace the turbo!

To get a second opinion I took it to my local independent who confirmed the fault codes as P17964 (turbocharger pressure not reached). They could find nothing else wrong and said it was more likely to be a sensor as opposed to the turbo.

The turbo works most of the time, although I am sure low rpm response is much poorer than it used to be. It is also quite laggy. It tends to go into limp mode when accelerating in 5th or 6th gear when the engine speed reaches 2400rpm. It then cuts the turbo completely, and the only way to get the turbo back is to restart the engine. It seems worse when the engine is cold.

So, does it sound like vw are correct and I need a new turbo, or is it likely to be a sensor?
Has anybody else experienced something similar; what did it turn out to be?

Thanks,