Bear with this, it's information received from the victim, have not seen it personally.
A mates old fella has the above car which has developed a slightly strange problem. Sometimes (not all times!) when driving, the overdrive light illuminates and the car seems to enter a strange mode, that then starts causing it to "jump" through the gears (sometimes quite violently).
One mechanic said there was nothing wrong with the autobox, and an ECU read came back with a faulty cam sensor, which was replaced.
Another said it could be a dodgy earth, and made a new earth strap to the engine.
The problem is very intermittent, seems to happen over a long journey, and sometimes when under load (such as climbing a hill).
I know Ford auto boxes are crap at the best of times, so hopefully there are lots of people out there who know this to be a common fault.
Cheers for any help