1999-2009 [Subscribe to Daily Digest] |
![]() | [Main 95 Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
But you shouldn't... Posted by Larry West [Email] ![]() ![]() ![]() In Reply to: You can live without it, Janik, Sat, 11 May 2013 07:49:06 Members do not see ads below this line. - Help Keep This Site Online - Signup |
The "Hooter" valve is a bypass valve that routes compressed inlet air (i.e after the turbo) back to the inlet side of the turbo compressor (before the turbo) when the throttle is closed abruptly. The main purpose of the valve is to prevent hoses from being blown off, while also preventing the turbo from "stalling", or slowing down a lot. So, the valve helps keep the turbo spinning, so if you are on and off the throttle a lot, you don't have to wait for a stalled turbo to spin up.
In a race car, the valve would normally dump the excess pressure overboard, giving that "sneezing" sound. In a road car, you don't want that, and the car makers can't design it like that. One reason being is it would result in an overly rich mixture for a short time, which would not make the emissions trolls happy.
Bypassing keeps all the metered air inside the system, reducing the emissions impacts.
You may be able to do without on an LPT, but definitely NOT on an Aero.
BTW, the term "Hooter" comes from the sound a failing/failed bypass valve makes.
->Posting last edited on Sat, 11 May 2013 18:34:40.
_______________________________________ Current: 2002 9-5 Aero Kombi Cosmic Blue 2000 9-5 SE sedan, Imola Red 1990 900S Rose Quartz, Auto Past: 1999 9-5 LPT Combi 1999 9-5 LPT sedan 2002 9-5 Arc 1990 900 5-speed 1986 900 turbo Convertible 1991 9000 turbo 1980 99 GLi 1986 900 turbo 1986 900 S 1991 900 turbo 1984 900 turbo 1976 99 GL
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
![]() |
![]() |
![]() |
![]() |
![]() |