View Single Post
mark houghton mark houghton is online now
mark houghton's Avatar
Join Date: Jul 2008
Location: Central Washington State
Posts: 3,893
It is the stock recirculation valve internal piston slamming against it's stop. Put new gaskets in and be done with it.
Every time you get off the throttle, engine vacuum will pull and hold the piston open until you get back on the throttle and vacuum goes away. Thus, quick throttle punches in neutral will produce this sound.
Fix it, or don't worry about it.
Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, stock everything else. The result of a massive Pelicanite good will fire recovery effort. Truely an open book, ready for the slippery slopes to modification.
Old 09-17-2010, 01:49 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #10 (permalink)