Vauxhall Astra 1.7TD dead spot - ivan whitmore
I have a 1998 Astra 1.7TD which seems to have an intermittent lack of power/revs.

When I accelerate through the gears, sometimes it feels as if a rev limiter comes in at about half way through the rev range and the engine will not continue to increase the revs. It does not happen every time, but it is a little disconcerting when it happens on a slip lane entry to a major road. On other occasions the engine will rev smoothly through the range quite normally.

Has anyone come across this problem before and can anyone point to any likely causes and offer any suggestions please?