The banner above is an advertisment - if it asks you to download software, please ignore.
Site News - 3/26 M Car Covers (by State of Nine) | 12/12 Make Amazon Pay Saabnet!
Date: Sun, 03 Feb 2002 05:54:16 GMT
From: fristnopsamnet (Ramsey Frist)
Subject: Re: 9000 intermittent rough idle/stalling


In article <3C5C951A.C965CF97nopsamia-esprezzo.com>, danny <dannynopsamia-esprezzo.com> wrote: > Hi chaps/chapesses > > Recently my 1990 9000CDS (non turbo) has been idling erratically. It > comes and goes, and when it doesn't do it it runs absolutely fine, but > the next time you get in the car the idling speed can be all over the > place. Actually it tries to idle at 900rpm, but keeps rythmically > dropping to nearly stalling then recovering, and after a while it will > just stall. Coupled with this is the fact that it now nearly stalls at > speed under gentle acceleration, at any speed - you can be driving along > and the engine cuts out momentarily then recovers. At lights I have to > keep the revs up so that in the dropping phase it stays high enough to > not stall. > > The only thing that has changed on the car recently is that since having > a new front exhaust pipe fitted (flexible section from downpipe to cat) > it has leaked from the downpipe connection and had to be retightened > twice (each time blowing the gasket). Currently there is a very small > blow from the join. I checked the engine mounts as a possible source of > why the new pipe wouldn't stay connected, but there is no movement in > the engine as far as I can tell. Is it possible that the lambda probe > possibly getting wrong air measurements due to the small exhaust leak > can have this effect on idling? I have checked for vacuum leaks by > sight, all seems fine. Any other suggestions? Thanks. > > -- Its likely that the problem is with the "adaptive idle control valve" which maintains the proper idle by regulating air through the bypass around the throttle. On two of my Saabs these got sticky somewhere around 100,000 miles. If you are lucky a good cleaning with choke cleaner and Q tips will fix it. If it still acts screwy after cleaning it means the electrical commontator on the servo motor is burned in places and you might as well replace it. I was also once told by a Saab trained technician that the only symptom of the oxygen sensor going bad is an irregulor idle but I don't think that this would cause it to be as drastic as you describe. Good luck, Ramsey Frist

Return to Main Index
StateOfNine.com
SaabClub.com
Jak Stoll Performance
M Car Covers
Ad Available

The content on this site may not be republished without permission. Copyright © 1988-2024 - The Saab Network - saabnet.com.
For usage guidelines, see the Mission & Privacy Notice.
[Contact | Site Map | Saabnet.com on Facebook | Saabnet.com on Twitter | Shop Amazon via TSN | Site Donations]