Thanks Tom,

Thinking about it some more, I am more inclined to suggest it may be a driven plate (clutch friction plate) problem rather than a pressure plate problem. As I mentioned, it is engine speed sensitive, but only whilst the driven plate is engaged. With the car stationary, if the clutch is released at idle and then the engine is revved there is no difficulty in selecting a gear (reverse is a good one as it will make it quite clear audibly whether the gearbox input shaft is still spinning or not). If the engine is revved before attempting to release the clutch, then attempting to release the clutch and selecting a gear is impossible.

I am wondering if if the cause could be that some of the friction material on the driven plate is breaking away such that at higher rotational speeds the centrifugal force causes it to fly out and make contact with either the flywheel or pressure plate. Even when the clutch should be released this fault keeps the driven plate spinning. This allows sufficient drive to prevent gear selection and shifting. At lower speeds the centrifugal force is insuffient to keep the friction material in contact with the pressure plate or flywheel and therefore the drive to the driven plate ceases which allows for gear selection.

Just an idea anyway. Anyone got any other ideas?

Thanks,
Greg

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