Over the past couple weeks, I've noticed that my gas mileage has dropped a little. Nothing drastic. It normally hovers around 43.3 mpg. Now it's down to 42.6.

Cold this just be from the Winter temp. drop? Or is it something else?

 

Source: http://www.fueleconomy.gov/feg/factors.shtml

 

Also, oxygenated or "winter blend" gasoline can cause a 2-3% drop in fuel economy, which would be even greater than the 1.6% drop you're seeing. In the winter, the cold weather causes fuel to atomize poorly compared to warm weather, so the refineries use additives to help improve the vaporization/atomization of the fuel. While these additives promote better fuel burning, they don't provide energy themselves, so the overall energy content of the gas goes down a little.

 

In addition:

Colder air is denser, and takes more power to push through.
Cold tires do not roll as easily as warm tires.
Cold tires will often have lower air pressure than warm tires--this, at least, you can fix.

 

That is still pretty stellar mileage. I get like 25 in the city, but I drive the **** out of it.

 

That's partially a 1st gen/2nd gen issue as well. I don't think *anyone* gets 43 MPG out of an R50, no matter how they drive it.

 

True! Even so, 40's sounds better than most of the 2nd gen numbers I've seen around here.

I got as good as 39 in my R50 on a long highway trip.

 

I don't even pay attention to my gas milage. I just drive.

 

43??? I'd like to know your driving habits for sure. I get 30, but it's my DD and I spend a fair amount of time in traffic and stomping on the gas pedal. But yes, the above reasons could contribute to your mileage decrease. Also, you are talking less than 2% difference there. There's enough error in the fillup process to account for that difference. Actual full vs what you put in vs what was put in last time, etc.

 

Thanks for all the info, everyone.

The awesome gas mileage is one of my favorite things about my mini. I think the only real reason why mine is particularly high is because I do a fairly good amount of highway driving. I'm also getting close to mastering the art of coasting

 

Depending on traffic, I average 38-40 mpg per tank -- that's one of the reasons I chose a MINI. Had plenty of go-fast cars in my day, some costing multiples of the MINI. My TDI's could beat it in mileage (loved that low-end torque while getting 50 mpg), but none could compete when it comes to Smileage