914Audi

Mark:

A few things:

1) My mistake, it wasn't the rear wiper, it was the rear defroster.
2) I also noticed that the impact is greatest when the accessory is first turned on, and then it steps down. For example, the seats at high setting dropping to medium on their own.
3) I will check again tonight on the drive home and if I remember to take some pics.

Q5 TDI

Much longer warm up times in the severe cold, and more wheel spin in the snow lead to worse mileage.

My wife had a Prius. Before we sold it she could get 48 regularly in summer, but it would drop to 37 in winter - a bit different in the Prius case, the electric it would normally use to power the car and get better mileage, it was using to heat the seats, run the defrosters etc.

Anyway - my TDI mileage has dropped as expected, the last several weeks especially.