I maybe hearing a normal noise but wanted to check. My 2016 Vrs Tdi is bog standard engine wise except for a pedal box. I have noticed a noise not dissimilar to a dump valve but a bit warbly when sitting in the drive thru for Costa, happens every time the engine stops, I have stop/start on at the moment, the noise may have been there the whole time but gets reflected back of the wall of the drive thru. Tried to hear it at home but its quite open where we are and the sound is less. So my question is, is it normal or has something come adrift. 

Performance is normal. 

Mine does this. It is simply the noise made when the turbocharger is still spinning and compressing air. But there is nowhere for the air to go if the engine is stopped. So it makes a whooshing sound in the intake if that makes sense.

1 hour ago, Ecomatt said:

Mine does this. It is simply the noise made when the turbocharger is still spinning and compressing air. But there is nowhere for the air to go if the engine is stopped. So it makes a whooshing sound in the intake if that makes sense.

That makes sense completely, not used many drive thru's so only just noticed it after three years🤣.

Diesels don't have dump valves as there is no butterfly throttle valve to stop the airflow. I think as mentioned above those kind of noises are normal for the turbo to make.