gearbox problem - jumping out of 2nd gear
05-27-2010, 05:38 AM
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gearbox problem - jumping out of 2nd gear
Interesting niggling problem for all the time I've owned the car.
Sometimes, the car will jump out of 2nd gear into the neutral gate. Most often, it will if I'm actually going downhill in 2nd gear, coming up to an intersection or turn, put on the brakes to slow, and the car jumps out of gear into neutral. Only happens in 2nd gear. The downhill bit makes me think that the gravity and deceleration combine to let it drop out of gear (the stick is actually falling forward).
The car has done this for 20 years -- in the orginal service records there is an entry where the original owner had it into the local Porsche centre to try to track it down. Apparently, they had the transaxle apart, but couldn't find the problem.
Any ideas? Eric suggested a detente spring might have come off or is otherwise missing.
Not a big deal, it only happens occasionally (it did this evening), but thought I'd ask in case anyone's come across this before.
Sometimes, the car will jump out of 2nd gear into the neutral gate. Most often, it will if I'm actually going downhill in 2nd gear, coming up to an intersection or turn, put on the brakes to slow, and the car jumps out of gear into neutral. Only happens in 2nd gear. The downhill bit makes me think that the gravity and deceleration combine to let it drop out of gear (the stick is actually falling forward).
The car has done this for 20 years -- in the orginal service records there is an entry where the original owner had it into the local Porsche centre to try to track it down. Apparently, they had the transaxle apart, but couldn't find the problem.
Any ideas? Eric suggested a detente spring might have come off or is otherwise missing.
Not a big deal, it only happens occasionally (it did this evening), but thought I'd ask in case anyone's come across this before.
Last edited by Mark944na86; 11-14-2010 at 11:44 AM. Reason: more descriptive thread title
05-27-2010, 08:15 AM
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Bannana Shine
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A spring that eases strained relationships between two nuclear superpowers? 
Have you actually sat there in your driveway and slowly notched it into second, compared to say, 4th, to feel whether there's a difference in terms of force, smoothness, etc? Maybe even push it out of gear with just one fingertip and see whether you feel a specific resistance that you overcome and then suddenly the lever is released to neutral, or if the force you apply decreases linearly as you push it?
Have you actually sat there in your driveway and slowly notched it into second, compared to say, 4th, to feel whether there's a difference in terms of force, smoothness, etc? Maybe even push it out of gear with just one fingertip and see whether you feel a specific resistance that you overcome and then suddenly the lever is released to neutral, or if the force you apply decreases linearly as you push it?
05-28-2010, 12:19 AM
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It's strange though that the safety wire should really affect anything at all -- unless the bolt had actually backed out all the way. Had it?
It has me thinking that that there may be some linkage adjustment that is worth checking. There is a specified angle the gear stick is supposed to be adjusted to in the FSM (I think I remember that, anyway).
11-14-2010, 11:32 AM
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It only took me about 6 months to get around to trying adjusting the gear stick angle (to ~5 degrees off vertical, tilting backwards when in neutral gate, as per FSM).
It seems to have worked, or at least masked the problem to some degree. I tested on a hill I could always get the stick to pop out in when going down and decelerating to stop while in 2nd gear. Stayed in gear!
After reading other threads that describe this problem over the years, it seems the most commonly suggested answers were a) worn 2nd gear synchro, or b) detente spring adjustment in transaxle.
To tell you the truth, I was (and still am) somewhat sceptical the problem really is down to something as this simple adjustment, because (according to the service records) the mechanics at the Porsche service centre couldn't figure it out 20 years ago when the car was almost new. So I assumed the problem was non-trivial and probably would require a transmission expert to diagnose and fix the problem.
We shall see. But if anyone else is having this problem, you might want to check the gear stick angle. Clark's garage has a write on the adjustment procedure -- very easy. BTW, my adjustment angle was set about 90 degrees before the readjustment, which seems natural, but (according to the FSM) is incorrect.
It seems to have worked, or at least masked the problem to some degree. I tested on a hill I could always get the stick to pop out in when going down and decelerating to stop while in 2nd gear. Stayed in gear!
After reading other threads that describe this problem over the years, it seems the most commonly suggested answers were a) worn 2nd gear synchro, or b) detente spring adjustment in transaxle.
To tell you the truth, I was (and still am) somewhat sceptical the problem really is down to something as this simple adjustment, because (according to the service records) the mechanics at the Porsche service centre couldn't figure it out 20 years ago when the car was almost new. So I assumed the problem was non-trivial and probably would require a transmission expert to diagnose and fix the problem.
We shall see. But if anyone else is having this problem, you might want to check the gear stick angle. Clark's garage has a write on the adjustment procedure -- very easy. BTW, my adjustment angle was set about 90 degrees before the readjustment, which seems natural, but (according to the FSM) is incorrect.
