Thanks Steve,
I’d used a local garage for that diagnostic and I think he specified a different engine when he plugged it in. Anyway, all resolved now. Audi main dealer tried to rip me off. Diagnostic showed “Exhaust GasTemperature Sensor Circuit - Bank 1”, they insisted that they would have to remove the CAT to investigate further at a cost of £526.97!! I said no and took it to an independent Audi specialist who diagnosed the same fault and simply replaced the sensor! Problem solved for £300 including labour! They didn’t understand why the CAT should be removed when the diagnostic has indicated what the problem is! Just replace the faulty part, which is near the turbo apparently.
in addition to this, the Audi main dealer stated that my rear pads were 90% worn and both they and the rear discs had to be replaced, cost £475! They also said that both front bushes had to be replaced because they had small splits in them. I refused all work and took my car to the independent garage (which I will name if anyone wants to know). They were so professional and down to earth. Replaced the sensor, found my rear pads were only 60-70% worn and the discs did not require replacing. They also stated that the bushes were fine and pointed out that under warranty, Audi main dealers would never replace the bushes unless they were split all the way round.
I estimated that the total work at the main dealer including service and diagnostic would have been around £1,800. Total cost at independent garage £595 including VAT and TUNAP oil flush.
I will be recommending this independent service centre to all my Audi friends.
thanks again Steve.