Have a problem with my 2002 2.5tdi which is causing the turbo to overboost. There doesnt seem to be enough vacuum to close the vanes on the turbo causing it to carry on boosting when it shouldnt, especially when braking.
There is no fault with the braking system itself and the servo appears to be working fine.
Just recently had turbo cleaned as though sticking vanes was causing the problem but this doesnt seem to be the case, the vanes move very freely now. Also had new thrust(boost) sensor and vacuum control solenoid.
Any ideas people...........