When iam sitting at idle there is this noise coming from the tranny, but when i step on the clutch it goes away??? and when iam downshifting into second gear it grinds???? untill i put it in neutral and then back in second, it does this everytime...and when i put it in 4th gear it comes out of gear by itself and into neutral unless iam actually holding the stick and keeping it from coming out of gear... what is my problem here??