I recently purchased a 2002 Subaru Impreza. 2.5L non-turbo, 197,000 miles (but it came with a stack of service records 3.5" thick)
However, it has a vibration in the clutch pedal when shifting. The vibration can be felt, and sometimes heard as a 'buzzing' noise, and it follows engine RPM during shifts. So I tried some stuff:
When sitting still in neutral, there is no vibration when I push in the clutch, regardless of engine RPM.
When coasting in neutral, no vibration.
When driving down the road under power, no vibration.
Seems to only happen during shifts while getting the car up to speed. It's strangely better some days than others. I've had a few manual transmission cars in the past and never experienced this with them.
I'm guessing (or at least hoping) it is a throwout bearing. Is there any test I can use to isolate this from say, transmission input shaft bearing, transmission mainshaft bearings, or loose/damaged flywheel without pulling the transmission?
Thanks.