Thanks for the pointers guys.
I had a feel round the vacum hose and it seemed fine with no cracks.
Is it ok to just pull it off to examine it properly or is that a bad idea?
I had the RAC out today. The bloke thought it was a fuel starvation issue and not a misfire.
The car surges, with the revs rising and falling as you pull away. I suppose it's not really a misfire.
He advised me to change the fuel filter and put some redex injector cleaner in the fuel.
I have done both of these and it's just the same.
He said that if this doesnt cure it it could be a
issue which would be expensive to fix and wouldn't be worth it. He thought that it would be a case of throwing parts at it which would be very expensive.
Any further ideas beyond the vacum hose? I'll recheck it anyway to make sure.