amafrank
Well-known member
now that we're finally over 50 deg here in Indiana the mileage in the GSW has finally climbed above 40mpg real and 43mpg according to the dash. Last fillup showed 45mpg dash and turned out to be 41.8 real. This is the first time I've gotten better than 40mpg out of this car since december when I got it. Yesterday with the temps in the 70s I averaged over 49mpg according to the dash on a trip of 120 miles of varied town and country road driving which is shocking to me. Why the difference with temps?
My 2006 Jetta Tdi sedan averaged over 41mpg for its whole 200K mile life regardless of outside temps. I didn't get better mileage in the summer than I did in winter. I got better mileage on long trips and when I kept my foot off the pedal. It did over 50mpg when I did a lot of interstate driving without flooring it. 45mpg was normal for the road, temps didn't matter. The 2009 Jetta Tdi Sportwagen is the same. No difference summer to winter.... What is the reason behind this? Seems counter intuitive when colder air is denser and keeps combustion temps a bit lower along with better air density in the cylinder. Should be better mileage in winter?
Frank
My 2006 Jetta Tdi sedan averaged over 41mpg for its whole 200K mile life regardless of outside temps. I didn't get better mileage in the summer than I did in winter. I got better mileage on long trips and when I kept my foot off the pedal. It did over 50mpg when I did a lot of interstate driving without flooring it. 45mpg was normal for the road, temps didn't matter. The 2009 Jetta Tdi Sportwagen is the same. No difference summer to winter.... What is the reason behind this? Seems counter intuitive when colder air is denser and keeps combustion temps a bit lower along with better air density in the cylinder. Should be better mileage in winter?
Frank
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