Difficult to shift into first and reverse when stopped (worse when car warms)

[eZ_Harry]

Car: 2002 Version 8 STi 6MT

Problem:  It can be difficult to shift into first and reverse gear (no other gears are affected). If the car is even slightly rolling, there is no difficulty shifting into first or reverse gear. When I first start driving the car (engine is cold) it is relatively easy to get into gear, but after about 20 minutes of driving it gets much more difficult. At it worst a fair amount of force can be required to shift into gear.

Double clutching can help reduce the difficulty. Shifting into first while the car is coming to a stop completely eliminates the problem. If I am at a stop, shifting into second and then straight into first completely eliminates the problem.

Attempted Solution: To me this sounds like an issue of the clutch not fully disengaging from the flywheel. I have attempted to fix this by replacing and bleeding the clutch master and the slave cylinder. Unfortunately this doesn't seem to have resolved the issue.

Side note, I recently had the engine rebuilt and the mechanic said the clutch looked about half worn, so I opted not to replace it.

Could anybody explain potential causes for this problem? I'm confused as to why it only happens in certain circumstances such as from a stop, worse when heated etc.. The only heat sensitive part I could think of is there is still air in the clutch hydraulic system and that is expanding when the car warms... but i just bled the system.

[Loren]

It could be a gearbox issue, not the clutch. If it's a clutch issue it could be over-throwing rather than not disengaging. When at a standstill, try putting it in first gear with the clutch pedal only about 75% down... move the gear shifter slowly, and if you feel any crunching, press the clutch down a bit more until it goes into gear without crunching. 

Edited August 30, 2022 by Loren