Hello sweetie ;)
Not sure about the gasket mate.
And for the BOV I can't see why it would do anything to the car, it's still doing the same thing with one on and I've seen Twin Legs with them on before. But just to make you aware I've seen some people put a BOV on there car and then have problems not many just some, yet others will fit them like me and had no problems at all and that's with Impreza's :(
By the sounds of the pump I would say it's on it's way out or being made to work harder to move the fuel making it buzz. Sorry didn't really help that did it :D
And not sure what's happened to Miggs he's not been on for awhile I think he's started to have an affair with other forums :( tutut :)