xlilbluux

If you drive with AC off will you still get the same MPG as if were driving with A/C on?

gochan

no, you should get better gas mileage

xlilbluux

So a/c waste more gas right?

pgould

This would be why the EPA gets higher gas mileage than what most folks see...they turn the A/C off for their tests.

terse

I heard that if you drive with your windows open...it's basically the same thing as driving with the AC on...cause the drag of the wind (resistance) makes you drive harder and wasting more gas.....but don't quote me on it.....it's just what I've heard..i don't know if it's true...

pgould

I've read the same thing regarding having your windows open vs. A/C on...in Car and Driver, I think? Had to do with today's cars being more aerodynamic so that the load presented by running the A/C compressor was less than the drag created via the open windows. But I think it's only true at highway speeds...

Is there an automotive engineer in the house?

04acura tl

you do get better mpg's with the windows up and air on over the windows down!! I believe that is true for speeds over like 30mph

dsc888

You are right. Click and Clack, on NPR, answered a similar question and said that you save more gas by using the AC with windows up at freeway speeds. You save more by opening the windows at city speeds. Of course, you save the most by keeping your windows up and not using the AC but would you want to in the heat of the summer?

dsc888

pettydw

I have not noticed any highway mileage or mixed mileage difference between automatic and a/c off (windows up). The a/c drain may be less than 1 mpg in these conditions. Stuck in stop and go traffic, with the a/c at max'd out may be different.

Road Rage

Actually, it is because their tests are not typical of the long idle times of increased traffic density, compared to when the EPA protocols were developed.

But it is true that running without the air will increase fuel economy - that is a no brainer, except at highway speeds with all the windows open, where the increased aero drag evens things out.

donkeykang

...i drive with my windows down whenever i can...no wonder i get terribel gas mileage...