Be aware that fuel economy on new TDIs goes way down in the winter. Yes, there was a relfash - VW trying to appease the EPA - but it doesn't seem to affect fuel economy much.

How long is your drive to work?

Take a look at my fuelly, you'll see our Passat's fuel economy tank when it gets cold out. Every time it's cold started it uses extra fuel to warm the emissions components.

Passat TDI (Volkswagen Passat) | Fuelly

-J

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.