the only way you know its knackered is if it wont idle on its own
with mine when you started the engine and let it idle it would just rev all the way up to 4k and just hold at that. hence how i knew it was banjo'd!
ring RadiCool VW. they are very reasonable i've used them loads of times to get parts sent over to me in N.Ireland and also in the Isle of Man
Radicool VW
Unit N, Long Meadow Works, Ringwood Rd, Three Legged Cross, Wimborne, Dorset BH21 6RD
Tel: 01202 823060