Hi, was wondering if anyone could help with why I can’t shift into any gear while the car is running. 1968 mustang fastback, 6 cylinder 3 speed manual. Starts up no problem, clutch feels good. Been sitting in the garage about 6 months but no issues last time driving. Any help would be appreciated

 

If you start it with the clutch in, and in 1st or reverse gear, does the car want to move? (be careful if you haven't tried that yet).

 

Clutch doesn’t need to be pressed for it to start. But I did shift it in 1st gear while off then started the car, it jumped then stalled regardless of the clutch being used….

 

Your clutch isn't disengaging when the clutch pedal is pressed. You will need someone to help you who can push the clutch pedal while you watch the movement. Typically the failure will be external to the bell housing and observable from above with the hood open.

 

Great, thanks for the help