Date: Thu, 18 Apr 2002 23:00:50 +0100 From: "SimonJ" <menopsam.com> Subject: Re: whoosh between gear changes
"Grunff" <grunffnopsam.com> wrote in message news:3cbc8f9b_1nopsam2.vip.uk.com... > > "A&M" <andymegnopsameycheese.freeserve.co.uk.no_spam> wrote in message > news:a9hso9$fh4$1nopsam5.svr.pol.co.uk... > > My dump valve has just started making noise between gear changes when > > accelerating hard > > > > saab 9000 CSE 1994 LPT > > is it normal for you to hear the whoosh or is it knackered > > (standard black bosch recirculating valve fitted) > > On my 9000, I can always hear the whoosh, but on my 900T16, I can't, even > though it's the same valve. Are you sure it's just started, or have you just > strted to notice it? > > To test the valve, pull off the small 1/4" hose (not at the valve end, at > the other end), and suck on it. It should hold vac. If it doesn't, replace > the valve. > > Grunff > > If you can hear the 'whoosh' then the valve is working. The valve normally vents back into the low presure side air ducting, which muffles the noise, so it sounds like the vent pipe from the valve may have come off, allowing you to hear it work. This needs checking, as it will allow the engine to run lean, as it will suck in air after the air flow meter.