Hi

There is an intermittent buzzing/vibrating sound coming from (I think) the fuel tank of my 2017 S60. It occurs when the car is moving and stationary (with the engine running). If I open the flap where the fuel cap is, the sound is really quite pronounced, so I am fairly sure it is from within the fuel tank or very close to it.

I thought it may be the fuel pump, but the Volvo spare parts person thinks it is more likely to be related to the fuel vapor system (possibly as reported in this thread) because the car has only done 30,000 miles and they don't sell many fuel pump replacements (they haven't inspected the car).

Does anyone have any ideas how to diagnose this?