I have a w reg A170 CDI it is a tiptronic automatic (not sure if this is semi auto or auto.) The gearbox seems to run fine except it won't go in to 5th gear. 1-4 work perfectly but once it hits 80mph it stops and stays in 4th. There is no F on the dashboard and it runs through 1-4 fine but it is as if 5 does not exist.
Anyone got any ideas?
Anyone got any ideas?