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Discussion Starter #1
I've had my 900 for a while now, and recently it started stalling on me while driving after hesitating/bucking a bit. Even if I take the car out of gear, the engine revs up, and then drops well below idle by itself, and will eventually stall (though, at times I can drive for an hour with no problem). The other thing I've noticed is that, when accelerating, the car has great acceleration up to about 3000 rpms, when it suddenly doesn't seem to accelerate nearly as quickly; this is especially noticeable in 5th gear, when I sometimes have trouble getting the car to accelerate from 75 to 85 mph - it just doesn't seem to have the energy.

Clearly, both of these problems are troubling me, but I'm not really sure where to go from here... thanks in advance.
 

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Kind of sounds like you're fuel pump is on the way out.
 

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Sounds to me like AMM mixed with low vaccum possible an O2 sensor as well. I had the same problem changed the AMM and it is a lot better still bucks a little but think its the O2 sensor
 

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Can I suggest you look at both issues separately. I suspect the two may be unrelated. Start with simple-to-check things.

For the idle/stalling problem, check that the Automatic Idle Control valve is functioning. It sounds like it works some of the time. Suggest you remove and clean it out with carb spray. The gunk accummulated inside might be preventing the stepper motor from adjusting the idle continuously. It's easily accessible and takes 15 minutes to remove, clean and reattach.

For the lack of power above 3000rpm, check for obvious leaks/malfunction in the turbo/vacuum piping system. You might have:

1. A leak in piping/connection anywhere after the turbo compressor. Check that turbo and vacuum fittings are tight (i.e., more than just "snug"), especially the 3 rubber bushings around the throttle manifold. Positive pressures during boost, above 3000rpm, may cause less-than-tight bushings to pop out, and settle back when boost is removed.

2. A bad turbo bypass valve. If the valve opens prematurely, or is stuck open, you're going to lose boost when the turbo spools up. The valve is not that accessible.

Tell us if there any other symptoms and we'll try to narrow it down for you.

Oh, welcome to Saab Central.
 

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Discussion Starter #7
Thanks for the welcome :D The dead cat is definitely a possibility - the poor car has to sleep outside, who knows what gets into it...

The only other "symptom" from the turbo that I can think of is that the turbo guage never reaches the red area - only through the yellow. Should it be reading higher? Also, what is the AMM (sorry, stupid question?)
 

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goosed88 said:
The only other "symptom" from the turbo that I can think of is that the turbo guage never reaches the red area - only through the yellow. Should it be reading higher? Also, what is the AMM (sorry, stupid question?)
I should only go to the top of the yellow, but never into the red.

The AMM is the Air Mass Meter. It's the metal box just above the air filter, and has a connector going into it.
 

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There is a way to kinda test if the Air Mass Meter is working or not. You take it off and take an ohm meter to pins 3 and 6, it should read 380. But it is not super acurate. Mine was bad and was readed something like 900 or something and it didnt work at all. havent tested the new one yet. But the saab has one of the worst AMM ever. Every Saab mechanic that I have talked to have told me that. Good luck
 
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