Hello bodgerd. Open the bonnet and see if there is a piece of foam missing from the area above the air filter. I do have a picture, but as a newbie, I cannot upload them so I "borrowed" one from "Changing Your Air Flow Meter, 'How To' guide with Pictures" ckick ^_^ http://www.bigtrucker.co.uk/images/maf/001.jpg It would be the piece of foam next to the rubber lip. I know that it is small, but it does make a difference. But the sound would come from the small triangle window in front. If the sound is from the door area, then I have no idea. Decappo