Would search for this (but that's not available to us mere mortals )

do dump valves leak??

reason i ask is when i drive slowly along central barriers on duel carriageway i hear a sound that i can only describe as a chattering air escaping sound....??? no foot on the clutch just coming off the revs in slow <10mph traffic.

im a big kid at heart and quite surprisingly like the sound of the VTA

BTW the valve is a Forge

i assume that the valve works with some sort of diaphragm can these split? and if so is replacing an easy DIY job?

 

it sounds like it is bordering on the pressure for it to dump. i heard some else say theres does it

 

Search function has been working for about a week. But ssshhhh dont tell anybody