Passat TDI 100 loss of power

[T&GRay]

My Passat TDI 100S estate 2002 sometimes goes into go slow mode. When under high load high gear situations such as motorway overtaking (not thrashing though). It is as if the wastegate just stops open and I lose all turbo assistance, the only way I can get it back is by turning off the engine and restarting it, no fault codes show in the memory though, any thoughts anyone?

[Coupe_Daz]

Air mass meter is the obvious first stop, but I will stick my neck out and say its not that as it does sound as if the car is overboosting and going into limp home mode.

This could be the fault of the turbo boost control solenoid (N75 valve) which is located in front and to the left of the cambelt cover.

If this does not cure it, it could be a wastegate fault and the only option dealer part wise is to replace the turbo. There are places that do just the wastegate seperately though.

[audi-almeister]

Roadtest the car and disconnect the air mass,there should be an improvement but not a great deal to confirm air mass @ fault,

As for the N75 valve, a common concern for these is a broken wire in side the connector, un plug it and pull the connector sleeve back,the wire breaks at the female terminal end. Makes sense if your keying on and off.