Matty Mooling

Is it true that you would use more gas with all your windows down than if you would just turn on the AC. The person that says this gives the reason that with the windows down it causes too much drag on the car and makes it work harder than if the AC was on and the windows were up. Is this true or false?

macdaddyslomo

false....however you would get more wind in your face anyway with one window down rather than all of them....it's an air pressure thing

gcs118

They actually ran a segment on the news about this a few years ago. They determined that under 55mph, windows down is better, but above 55mph the A/C is better because of the drag.

Roddimus Prime

sounds about right....gcs.

rustychops41

I saw that story too. It's mainly due to modern cars being much more aerodynamic than their predeccesors. In "the old days" windows down was better than AC on. Now it's better with windows up and AC on. And of course, windows up with AC off is even better when you can do it during the cooler times of the year

Blahbbs

It seems that a reasonable compromise would be to tilt up your sunroof (if you have one) and turn the dashboard fans up. The assumption is that the tilted sunroof really ends up being simply an exhaust point for the cabin air without spoiling your aerodynamics too much.

Question: sometimes I'll run the A/C with fresh air, then when the temperature cools off enough, I'll turn off A/C and immediately switch to recirculate until the air gets warm/humid. Then I switch back to A/C w/fresh air. Any idea if I'm putting the system under any undue stress by doing this? I seem to be getting about 31-32mpg with 80% freeway miles as it is, so I probably am being too ****.

FIJI 3779

I find that I don't need to use A/C if I tilt my sunroof and turn the defrost on feet and windshield. The air is just as cold as A/C.

03ESPro

I hate to tell you this, but with the defrost on feet and w/s, your a/c IS on. Our cars, as do most, override the A/C switch in certain positions.

FIJI 3779

That's good to know...what other positions will override the A/C?

03ESPro

I don't remember what the others were, but if you search you can find them, and also find out how to disable the switch. If you just want to check for yourself, put the car in park and open the hood with the motor running. Then, turn the A/C button off and move the selector switch. You should be able to hear the compressor click when it engages, meaning the A/C is on.