hi need a bit of help. the car has been leaking gearbox oil at the rear of the transmission and felt a bit grabby in the first few gears at times.today on the motorway it wouldn't go into overdrive at 70mph. i slipped it into neutral then back into drive, problem sorted. well until i had to stop, then stuck in 2nd, tried the neutral thing again and lost all gears. spoke to a specialist and he said it was the multi plug needing replaced but he couldn't do it for a few weeks, he topped up with oil and all is well at moment. i got the plug but don't know where it goes, doesn't show it in the haynes manual. would be very grateful for your help. its going to mechanic next day or 2 but he never really works on automatics. sorry for being so long winded but need fixed asap as i use it for taxiing. thanks