A woman called in today with a 93 Saab 900 that she said had little to no power right after start up. She claimed if she shut the car off then restarted the problem went away, which seemed to baffle you guys. I used to drive one of these cars (past tense, thank GOD) and had a similar problem. My Saab, however, would do this after one of the tires had spun on a slick surface. Often if I shut it off and restarted it would go away, but occasionally it would have to sit overnight to restore itself. After a little research I learned that this model is equipped with something called “Limp home mode” which may be somehow tied to the TCS ( which is TERRIBLE on this model, btw). Google “Saab Limp home mode” and you’ll find some repair options.
I have currently a 1997 Saab 900 and had very similar issue.
TheSaabsite.com was invaluable in researching an diagnosing. My symptoms, just like the original caller would remedy themselves after a restart, and were tied to several systems resetting themselves after restart - throttle, air intake, engine mounts.
Throttle cable adjusting sleeve had broken and would flail about and confuse the throttle position sensor; also a thorough cleaning of the throttle plate produced noticeably smooth acceleration. Investigate the black sleeve screw the adjusts the slack in the throttle cable, perhaps just need to take out slack.
In the air intake system, my rubber intercooler hose was cracked and would require higher rpms to reach any acceleration.
And lastly (perhaps not directly related to the original caller) is engine mounts, the produced substantial lag in initial take-off due to slack caused by engine rotating in the engine bay (and a nice clunk when the clutch was pushed in releasing the torque on the engine, and returning it to its resting position).
Got all this maintenance taken car of, car runs great! Love my Saab!
Also note that “limp home mode” only occurs on later model 9-3 saabs 1999 or 2002 onwards and was not equipped on Saab 900 models of the 90’s
To disable limp him mode one would have to actually, manually reset the throttle pulley and won’t allow the driver to accelerate past 30-40 mph, and the 900’s don’t have this secondary pulley (originally I thought this was my problem as well, only to find I didn’t have one lol).
When I listened to this call – I don’t have any experience with SAABS – but I thought it might be the auto-transmission on the fritz. If the xmission fluid is contaminated with bits and pieces of seals and metal shavings, these might get churned up and plug up passages in the control mechanism when driving and the fluid is being circulated, and when the car is stopped, they sink to the bottom of transmission pan. That would explain why it seems to work ok at first, then after driving, starts to have problems. Just an idea.
I believe I experienced the same problem. I’d start my '97 Saab 900, put it in gear, step on the gas, the engine would rev and I’d barely move. Essentially the car felt like it was starting in its highest gear. This was typically accompanied by a Check Gearbox and Check Engine light. I’d shut the car off, wait a moment, restart, and all was well again (idiot lights would remain on for 3-4 ‘starts’). This issue became progressively worse over time. LIke the caller, it wasn’t an issue in reverse. My reliable Saab dealer diagnosed this as a Gear Selector Switch fault, which for about $850 was repaired. Haven’t had a problem since.