Sorry, the technician wasn't any more specific - I did try to get a bit more detail, but the chap was up to his neck in work. I only know that it was to do with the EGR system. Apparently, it was carboned up very badly. I admitted that I tend to change up as soon as possible and that, in order to minimise fuel consumption, I tend not to thresh the engine. The advice was to 'give it a bit more stick every so often!'. I think the appropriate term is 'an Italian tune-up!'.

Without a doubt, the car runs significantly better since this operation was carried out. As it didn't seem to add anything noticeably to the service bill, I'm even tempted to get it checked out as a routine every couple of years.

"Any update on this vibrating/shaking problem"

Just dropped by and noticed that this thread is still going.......

It's some 8 months now since I reported that the vibration problem in my car has been more or less sorted (see above posts). Occasionally, there is a slight recurrence of the vibration, but this is not really a problem - I normally, say, drop a gear, give the engine more revs and go more quickly through the suspicious rev range. If pushed to quantify the efforts of the garage, I would say that they have given the car a 95% cure.

Also, I tend to rev the engine more through the gears as I am accelerating and I tend to cruise at 70 (+ a bit) rather than 'no more than 60'. I can still achieve 60mpg on a run. Additionally, when driving on motorway/dual carriageway at a lower speed and the car hits a slight incline, then the engine revs are inclined to drop rapidly into the 1800 area where the vibration may occur.

Driving back to Bury St Edmnds last night after playing at a gig near Canterbury, my mate took over the driving for the last 50 miles, and he didn't observe any sort of vibration issue. He normally drives an Octavia 1.6 diesel.

An unrelated problem that worried me greatly with the car was hellish stiffness of the gear-lever, also reported previously on this site; sometimes it took two hands to change gear!!! Web searches warned that the problem could be anything upto a totally duff gearbox. The same garage sorted the problem in an instant - all it needed was lubrication on the linkages costing peanuts to sort out while it was in for service.

If you live anywhere near central East Anglia, I'd be happy to recommend the garage - they really do seem to know what they are talking about!