hi mate,if its only 4th gear at fault then its almost certain to be a internal gearbox fault,possibly selector or detent plunger though on some gearboxes it has been known for the reverse light swithch to cause selector problems.....i am not familiar with this vw box so i would suggest you trying to prise some info out of ur local main dealer or even a independant transmission specialist sometimes they will help!
paul, April 2009
