One problem related to crankshaft position sensor has been reported for the 2000 SAAB Aero. The most recently reported issues are listed below.
My 2000 SAAB 9-5 Aero wagon has a problem of occasionally not starting. You can tune the ignition switch and power comes on but the engine will not turn over. If you allow it to sit awhile, then it seems to start. I replaced the crankshaft sensor, but it still does this. I noticed there may have been recalls.