Bit of an update on this, as some of you know the Audi turned out to have an electrical fault and despite putting it into 4 different garages no one managed to find what was wrong with it.
It was a strange fault that only came on when the car was idling but caused a terrible miss fire which would clear between 30secs and a minute after driving but would then reappear as soon as i pulled up at a junction or lights and back in idle.As i said no one could find the fault and kept mis-diagnosing it with something else which has cost me a few bob over numerous months.
Now just over a week ago i left a rude comment on Audi UK post on facebook complaining on how good they were selling them but not at fixing them - Audi UK contacted me and asked what my problem was, so i explained the story and they arranged for me to have my car looked at at a specialist center and said if they could not find the problem there would be no charge. So i thought what have i got to lose and today it went in-
Full diagnostic and free health check.
They had the car for 8 hrs and FINALLY found the problem--- a bloody dodgy injector on no 6 cylinder (after all that)

And on the free health check they found a broken spring near side rear, which they reckon has only recently gone (bugger)

and my engine oil needed a top up as it was only just above minimum
They said the injector was very intermittent and they only found it when they took the car for a run whilst plugged in to diagnostic and the ECU was not storing the code.
So i quite happily paid them £60 for finally finding out what was wrong with the car.
Now they also gave me a quote to put all of the above right
New injector fitted - £390
New rear springs fitted (pair)- £670
1 ltr of oil to top up engine to max level fitted- £50
Grand total of £1110 and if i wanted to leave the car with them they could do the work tomorrow.
I BET THEY BLOODY COULD 
I will be getting the work done but not at those prices.( i am swotting up right now- you tube and audi forum)