91 Saab 9000 possible vacuum hose problem

[dak83]

I'm a newbie.....I have a 91 saab 9000 turbo and while pulling into the driveway, the car turned off once the rpms got down to about 1000(there was no studdering or funny noises, it just shut off)...provided i keep the rpm's high the car will drive (it seems to idle ok as well, from a cold start)...i've eliminated the ignition cassette and was told maybe a vacuum hose...i looked and don't see any damaged hoses

[its_tricky83]

Originally Posted by dak83

I'm a newbie.....I have a 91 saab 9000 turbo and while pulling into the driveway, the car turned off once the rpms got down to about 1000(there was no studdering or funny noises, it just shut off)...provided i keep the rpm's high the car will drive (it seems to idle ok as well, from a cold start)...i've eliminated the ignition cassette and was told maybe a vacuum hose...i looked and don't see any damaged hoses

Or the Bypass Valve stuck open!!! Quite common.

[Superaero]

Or a dirty throttle plate which interferes with the AIC valve's ability to maintain a constant idle speed. This is more common on older SAAB's. Fuel Injection throttle plate cleaner is the solution here, assuming the hooter valve and all other vacuum lines are OK. The dipstick tube and cap leaking can also cause problems.