Are other drivers experiencing worse fuel economy after the emissions fix?

I had the emissions fix on my 2013 Volkswagen Passat 180PS three weeks ago. My trip is now showing a consistent 7 per cent worse fuel consumption and the burner is coming on more than it has ever done in the last two years. The DSG is slower to change down. I can't prove any of this, and the dealer says it isn't happening. Is this a shared problem?
I had a meeting with senior engineers from Wolfsberg on Wednesday. The reason is that achieving lower NOx creates more soot and that extra soot needs to be burned off by the DPF which uses diesel to burn it off. However, the German KBA certification for the NOx emissions fix demands that power and torque are developed at the same revs and that the engine uses no more fuel and emits no more CO2. The engineers got round this by employing 2016 technology on what are 10 year old engine designs to improve the fuel consumption of the engine to compensate for the extra fuel used in regeneration. But if an engine has worn injectors, a worn EGR valve or other age related wear it might not respond to the new software, so back to the dealer for a second fix.
Answered by Honest John on

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