Temperatures drop, MPG goes up
 

Got my best MPG for city driving. The number itself is not impressive, but when you consider my driving conditions, its not bad for the car and conditions.

So yea I got 24MPG in my 1989 Camry 4 cylinder auto in the City. Average one way trip = <2 miles, lot of traveling during rush hour. Lots of lights etc. I've gotten as low as 19MPG. I think the reason my MPG went up is because I have not had to use the AC at all. During the summer you die if you don't use the AC. It gets up to 115F!

I guess I'm probably one of the few that gets higher MPG during the winter months than summer.

I noticed that my FE improves in the fall, peaks in winter and drops off again in the spring again, all without using AC. Cold air definitely helps my FE. AC in the summer is a killer but that's a separate issue.

Here in Salt Lake City my mileage goes down about 7 to 10% in winter. We switch fuel formulations in the winter (too many high particulate days in winter), I presume the winter fuel has less energy than summer fuel.

Yeah, my fuel economy here in Flagstaff drops in the Winter with colder temps and winter fuel (?). I haven't managed to get 24 MPG out of my Mustang, yet. I don't know what I'm doing wrong...

Same here in N.O., mpg goes up in the winter. I think it is the less humidity in the winter and more regular burn in the engine. It could be something else. However, I feel it over my body when it's darn humid outside even the car need more gas to move forward. I see a difference of 5mpg to 7 mpg increase.

Hi,

"Cold" may be relative? And humidity decreases aero drag, all else being equal.

You guys who are seeing increased FE in the winter -- where are your fuel logs?

Sissy. :p