I have a 1997 Vectra V6 cdx auto. When the car is cold and I select drive and then reverse or 3,2 or 1 the dash display says "auto gearbox" and the car stays in 3rd gear and goes into D and R very hard.If I turn off ignition and restart the fault goes away untill I select R, 3, 2 or 1 again but this only happens when the car is cold when its warm it seems OK. Has anybody got any ideas please? Thanks