Does anyone know if smart has made any computer upgrades or program changes to the 2010 smarts? I have never had mine back to the dealer and am wondering. If I call the dealer, you know what they will want to do, esp when they charge $129 for an oil change on a smart car. lol
My gas mileage had dropped about 10mpg the last two fillups .. that is what has me thinking...
For your question I think you will have a better chance of finding an answer at a smart specific site. However, I think most of your drop is due to winter. This year has been colder than previous ones. So winter's effect on fuel economy has been bigger. Then throw in some traffic due to snow.
Spring is here, and we should be getting summer blend gas soon. I wouldn't worry until you can compare numbers with last springs.