cheers flapper. Had this
problem really since buying the car in oct 04. Have had MAF cleaned once then I made them change it the second time. Had a coolant level sensor and coolant temp sensor replaced in my ownership too. Still does it. Coilpacks seem fine, VAG-COM has no errors.
TBH Sparks are my last option. I picked the car up from SEAT and they "did" the 40k service at the time of collection, so the plugs SHOULD have been changed. However, I am somehow doubting that the service was done properly as the oil on pickup was terrible (queried this with them but they gave me some story blah blah)
Also had TB cleaned, realigned numerous times, and still no luck in solving
problem. It is REALLY apparent after a journey, I sit to let turbo cool for a bit and about 10seconds after stopping and letting car idle the car sounds like its gonna stall, drops to about 650/700rpm then jumps back up to the 1k mark briefly before returning to the 800rpm idle speed (all approx figures there)
I just thought that if my car has now done 51k, i could try changing the plugs and see if it helps. I understand that the NKG's are recommended when the car has been remapped anyway...