I cleaned my K&N panel filter on sunday, and I have noticed a lot more dump-valve type noise. Don't know if it was 'cos I cleaned it, or perhaps my recirc valve wasn't working before.

It's a massive difference so don't see how it could just be the clean. I've never been able to hear *any* dump valve hiss before and I have had the K&N for quite sometime.

A wile ago I thought that the recirc valve wasn't working and fitted the boost meter to the throttle body to see if the boost was going way up when I shut the thottle but it seemed to drop quite quickly as if the recirc was working so I did'nt worry about it.

Any ideas?

Perhaps I haven't put the lid back on properly on the air box????