Rev Problem

Hi

Im having a problem with my Skoda Diesel 2.0 ( 62 plate) which the Dealer and Halfords can't find the solution for.

The issue is intermittent, but occasionally my car stalls when I go into neutral or stop. No warning lights come on, the revs just die and the car then has to be re started, which it usually does ok

When it does this the rev counter is all over the place,  and recently has started bouncing when the engine is at idle. It'll do this on one day then the next be absolutely fine...recently I went two weeks with no issue then the next day it was awful again. Skoda ran a diagnostic but found nothing.....dealer said it could be dodgy fuel????

Only had two 'recent changes to the car....New EGR value and throttle sensor changed.....

Having read through a few forums....the problem could be anything or everything....anyone else had the same issue, and could point me in the right direction.

Matt