The Camaro Club (UK)

I now have a different daily since 3rd gen, it's a 2.0t diesel Audi. Over summer i was getting great mpg - 50 -55 on my normal commute. It started going lower as it got colder and now is about 42 on the same commute.

What's really bad though is some days it's awful - 10mpg for most of the trip, if i'm lucky at the end it might 30 if the road is clear, therefore no stop start.

Any thoughts about why the mpg has gone down by 10 or so in the colder weather and why some days it will be as awful as 10 for the most of the journey? My commute is mostly on the motorway and it's usually clear, so i put cruise control on at 70.

It's actually at the dealership today as it's under their extended warranty, and when i explained it to them, they said it's likely because i have the defoggers, heated seats etc. on to which i said no, i actually don't. I drove in the cold one morning to test it out - no heaters, fans, demisters, nothing.

It has a display that shows mpg's, it has a block that shows trip average and top an arrow that shows instant (i.e. throttle position). So on the motorway, the arrow would be on 60 for the journey, but the average bar would be on 10 and barely shifting. Normally the average climbs pretty fast towards the arrow once on a clean run, but it just sits there on the bad mpg days. No idea what's going on, wonder if there's any insight into it?

Cheers!

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