Which is it: transmission, clutch, or slave cylinder?

Question

I have a problem with my '92 Geo Prizm 5-speed manual transmission. I could use some advice from someone knowledgeable about manual transmissions.

Here are the symptoms:

1. DURING cranking, in Neutral, the car races forward as if in gear and it will only stop rolling if I push in the clutch. Stuck in gear maybe?

2. My car is parked in the driveway on an incline without E-brake on and it won't roll backwards, I can't even push her down the hill. Only when I push in the clutch will it move. Clutch binding?

3. And lastly, with the engine off I can shift into every gear fine except the shifter will just barely go into first.

Additional info: clutch fluid is level and I bled the slave cylinder, no help, I put a new clutch assembly on 2000 miles ago. Tranny was about half full on gear oil when this happened due to leaky axle seal. I need to know if the tranny is shot or if this is a clutch issue.

Answer 1

DURING cranking, in Neutral, the car races forward

The transmission is not in neutral, no other explanation.

Check the shifter linkage, it may be out of adjustment, or bent. Those are the most likely causes IMO based on the fact that you put a clutch in the vehicle and the linkage would have been disconnected and reconnected in that process. The transmission could be internally stuck in gear but that's less likely, but possible if you have had a bearing seized from the low fluid levels you found.

Only when I push in the clutch will it move. Clutch binding?

The transmission is in gear, the clutch is operating normally.

The clutch's only job is to connect/disconnect the input shaft of the transmission to/from the flywheel. When the clutch is engaged (pedal up) the flywheel and the input shaft are one. When the clutch is disengaged (pedal down) the crankshaft and the input shaft are not flywheel.

When the transmission is in neutral the input shaft isn't connected to the output shaft (the part connected to the wheels), so the clutch would not have an effect on the car rolling. With the transmission in gear (not in neutral) the tires are connected to the input shaft, and the input shaft is connected to the crankshaft via the flywheel. So if you start the car for instance it rolls forward, if you push in the clutch pedal it allows the car to roll, because pushing the clutch pedal disconnects the input shaft from the crankshaft.

And lastly, with the car off I can shift into every gear fine except the shifter will just barely go into first.

More support to my first point the shifter linkage is out of adjustment or bent.