Do you have any advice on dealing with Audi after the emissions fix caused increased fuel consumption in my A6?

I've just taken my Audi A6 in to have the emissions fix because Audi insisted that the performance, fuel consumption and CO2 emission will not be adversely affected. I instantly noticed driving back home that my car is now revving some 200 - 300rpm higher than it was before. I thought I'd give this a week to bed down, but it seems to be on all journeys I make the car is running faster and therefore using more fuel. I plan to take this up with Audi this week and would be grateful for any assistance to deal with Audi, who will undoubtedly be on the defensive. My car has been regularly serviced by Audi and is six years old with 57,000 miles. I had the timing belt changed out last year as well as the water pump.

Asked on 13 March 2017 by Neelesh bhojani

Answered by Honest John
VAG engineers say this shouldn't be happening, but evidence shows it is happening with some cars. I had a meeting with engineers from Wolfsburg on March 1. Basically the fix involves reducing NOx without any effect on power, torque, fuel economy or CO2. But reducing NOx means increasing soot, which has to be burned off in the DPF and requires additional fuel. To do this without affecting power, torque, fuel economy or CO2 the software changes the injection pattern, so fuel is now pre-injected, followed by a main injection, followed by a second main injection. Obviously, for this to work, the injectors have to be in tip top condition and the EGR valve stem must not be won. Problems have arisen when injectors were old, dirty or worn and where the EGR valve stem was worn. But, out of 480,000 fixes applied so far, there have only been 3600 complaints and out of them 60 per cent were noise related and 35 per cent were complaints about poorer fuel economy and EGR problems. They say that only 150 cases of problems after the fix remain outstanding. Every used car is different with different amounts of wear on its components. VAG devised the fix to work on several representative examples of used EA189 A6, and got it approved by the KBA, but, as I wrote, that does not mean that it will work on every used EA189 A6. As I wrote, the new injection cycle is supposed to feed extra fuel to the DPF without affecting the overall economy of the car. If it was not working for the vast majority of cars there would be more of a furore than there actually is, but obviously some owners are not so lucky, you included. I'm monitoring this all the time to try and assess whether the engineers from Wolfsburg were telling the truth, but I can't challenge what they told me on the basis of less than ten complaints a day.
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