I am the proud owner of a 1989 900 Turbo 4 cyl. 16 valve EFI and I need some help.
Well, here's the problem. To begin, she's hard to start, ( some days harder than others). When I finally do get her started, The engine will idle smoothly, but a little high while in the "Park" position. When I shift into any other gear i.e. reverse, Drive, and the others including back into Park, the engine appears to be hunting for a stable idle point. Uop and down, up and down, up and down. As I attempt to drive off, either forward or reverse, I must be careful because if I press down on the accelerator too fast or too hard, the engine will die off. No RPM's or anything. If I catch it fast enough, and let off of the accelerator, the engine will pick back up but still continue to hunt.
Two things I know for certain under the hood, are that the small vacuum hose on the PCV valve has been broken off and is not connected, and the platinum filament in the Air Mass Meter appears to be broken on one side. I am not sure if these two things have anything to do with the problem, but I know they exist. Also, I know for a fact that the Turbo has been mistreated i.e. revved too high and too soon after starting, and probabaly has not been allowed to wind down before shutting the ignition off.
PLease help me. I am learning a lot as I go along, but it's just not fast enough. She seems to be falling apart rapidly. Anything anyone can do to help me save this superb piece of machinery is appreciated. Thanks, Brad

Sounds like a mixture problem. If the air mass meter is broken I would expect the check engine light to come on (but someone could have removed the bulb). If I remember the filament in the meter only goes round three sides. The PVC pipe does need fixing or at least plugging both ends, check for any other vacuum leaks and stop them. Next thing is to check and clean the AIC valve (this controls the idle speed when additional load is added - eg aircon or headlights or engaging drive). Check out Townsends Imports Web site for help on these things.
http://www.townsendimports.com/
Dont worry about the turbo unless it is making noises other than a slight whistle which increases in pitch as revs rise.

Hi Adrian,

Hi Adrian,

Hi Adrian,

Hi Adrian,
sorry about the repeats. I treat this thing like Microsoft Word some times. Anyway, I forgot to mention that the check engine light is "ON". It sounds like this might actually be the problem. I was reading some info from another site called the SWEDISH WRENCH Saab Club and I got some procedures to get the "Flash Fault Codes" stored in the memory. I hope this works. I really need to know what is going on inside there. Any other info would be helpful. Thanks.

Yep if the air mass sensor if shot, the fuel ECU converts to limp home mode and engine check light comes on. Check those error codes before anything else. If you do change the air-mass sensor make sure you get the same part number, some of them are not interchangable (i.e. LH2.2 and LH2.4 are not the same). Good luck and let us know how you get on