We have an 02 Jazz which had the EGR valve replaced at under 20,000 miles to solve this problem. I am ‘in the trade’ and we get a couple of EGR faults every week across the whole range of makes. It always seems worse on vehicles which are used on short runs, or light throttle.
They can often be cured by giving them a good blast on the motorway with the engine hot, not of course exceeding the speed limit, but by holding a lower gear and accelerating/decelerating briskly for a couple of miles.
It is a fairly easy job to remove the valve and clean with carb cleaner, but in extreme cases the only solution is to change the valve.