I know this is a well discussed and common problem but I’m now experiencing this when I go out in the garage near the rear of the car when I take the cover off. Also when I took it for a spin today I noticed it when I was driving. There is no evidence of under bonnet fuel leaks so I wondered if the way the air swirls around the back of your head it could be the seal on the Aston type fuel filler cap? It’s about a 5 inch diameter cap. Anyone replaced this seal and can recommend a source? Thanks in advance.