Saving gas: A/C vs open windows

[laurie31]

Which is more fuel efficient? I read in one place to not use AC as it uses more gas, but I read in another place that open windows create "drag" and lower your milage.

So tell me, DISers, which is better? AC or open windows? I just wanna save some gas!!! (but not die of heat exhaustion in the process )

Laurie

 

[AllyandJack]

I have no idea, but I heard 55mph is the optimal speed for fuel efficiency.

Can you see me puttering along at 55mph on I-93 in MA?? That's a sure way to get KILLED.

I could never drive with my windows open....I have my music way too loud and I would annoy the other motorists.

 

[KingsFanInRI]

AC on low and windows up.

 

[monkeyboy]

Windows only open when someone "lifts a leg"

 

[Shutterbug]

Which is more fuel efficient? I read in one place to not use AC as it uses more gas, but I read in another place that open windows create "drag" and lower your milage.

So tell me, DISers, which is better? AC or open windows? I just wanna save some gas!!! (but not die of heat exhaustion in the process )

Laurie

I am a member of a car forum and we have had this talk. Todays newer cars are really for the most part built with aerodynamics in mind. I know my mazda 3 is. If you just lower the back window a bit the back of the car is really buffeted by the wind. From what I read, the consensus was that while driving on the highway (55-70)its better to have your windows up and a/c on to have better gas mileage. While around the city with lots of slow driving and stop-n-go traffic having the windows down is better.

 

[nuke]

Mythbusters did this test a while ago. They found virtually no difference in gas mileage no matter what the speed.

 

[doxdogy]

The news did a story on this a couple of weeks ago. For interstate driving running the AC will save on gas. In town driving you may save on gas by having the windows down. Down here in Florida, the AC runs all the time in the car in the summer.

 

[phorsenuf]

Windows only open when someone "lifts a leg"

Good thing I wasn't taking a sip of soda just then!

 

[Kermit]

I've decided to keep my windows up and the AC on (but on the highest temp that's comfortable) all the time. When I'm driving the slowest is when I'm closest to the cars around me, and I don't want their exhaust coming into my car and poisoning us. I'd rather have the AC working to filter the air some. I have been keeping the thermostat around 71 or 72 instead of 68, though.

 

[Feralpeg]

In Florida, it is dangerous to drive with the windows down. We have bugs the size of small missles. Those things hit the windows on a regular basis. With the windows down, we could be killed!

 

[Rock'n Robin]

I noticed a rise of about 1.5 MPG (almost one round trip to work) if I do NOT run the AC. I tend to run it more in stop-and-go. I ran it today because I went from my 87 degree classroom to my closed up black trailblazer and I could not take it.
I sing loud too. If I have to listen to that crappy bump-bump-bump rap music bass, they can listen to my 60s and 70s music for a minute.
Robin M.

 

[illini]

I have related question- Is it better to shut your car off or leave it idleing while getting out of it for a few minutes-i.e. dropping my son off at daycare?

 

[SillyMe]

I am a member of a car forum and we have had this talk. Todays newer cars are really for the most part built with aerodynamics in mind. I know my mazda 3 is. If you just lower the back window a bit the back of the car is really buffeted by the wind. From what I read, the consensus was that while driving on the highway (55-70)its better to have your windows up and a/c on to have better gas mileage. While around the city with lots of slow driving and stop-n-go traffic having the windows down is better.

I just read that in an article on Netscape last week.

 

[laurie31]

I have related question- Is it better to shut your car off or leave it idleing while getting out of it for a few minutes-i.e. dropping my son off at daycare?

This one I know

If you're going to idle for more than 30 seconds, it's better to turn off the engine.

Laurie
ps - thanks everyone for the input about the ac - I will continue to use it without guilt now

 

[illini]

This one I know

If you're going to idle for more than 30 seconds, it's better to turn off the engine.

Laurie
ps - thanks everyone for the input about the ac - I will continue to use it without guilt now

Thanks Laurie,
I have been wondering about that and I remember I knew a girl in high school who would run into the grocery store and leave her car running because she thought it took less gas than turning the car off and then on again. So now I know!!

Laurie - also

 

[Wishing on a star]

According to what I have learned...

Definately AC with the windows up.
My vehicle is designed to NOT be driven at roadway speeds with the windows down. Serious buffetting!

About the Idleing.... Cut off the engine... A warm engine restarts without too much extra gas. More than a couple minutes... cut the engine.

 

[caitycaity]

i'm guessing it really probably depends on the car and your driving habits. in my car, i notice a serious decrease in mpg when i am running the a/c, so i hardly ever run it. on the other hand, i have a convertible that i usually drive with the top down in stop and go traffic.