[LGB]

Mine does this, I assure you its not the pedal! Its the throttle body. Take off the small cover over the throttle linkage assembly on the inlet manifold, with the igntion off, open the throttle wide, then let go so it slams shut. See if it sticks when you try to open it next time, im pretty sure it will. You'll need to remove the throttle body from the inlet manifold & give it a good clean with some carb spray or something similar!