A/C's effect on gas mileage
 

Looks like mine loses about 2 mpg. Is that about the normal loss for running your A/C full time?

I too would like to know. I try to find out my mpg with it off, but I live in San Diego and I have little ones. When it gets hot my 2 year old tells me, "Dad please put on a/c". I can't tell her no. :)

i drove from nj to montreal ac on the whole way, still got 29 mpg going upwards of 80 mph

I read documentation about AC increasing gas consumption app 4 to 8 % depending on ambiant temperature, humidity, sun exposition, etc.

8% of 29 MPG would represent 2.3 mpg difference.

I get like 17 MPG (15-16 during the hot summer days with it on 100% of the time) with the a/c on like 75% of the time (usually at 70 or 72 degrees on the ACC). It's like 50-60% city driving and 40-50% highway-like driving.

I get like 18 MPG with the a/c on like 10-20% of the time. I drive kind of fast and crazy so if I leave the a/c off and ease up on the gas pedal, I'll probably get like 19-20 MPG mostly city.

I need to get a new exhaust system for better MPG :D Some new O2 sensors will help me too :)

ill throw this out there, my gas is usually the same year round.

in the cooler months i dont use my a/c but i have my windows down increasing drag.

in the summer i use my a/'c religiously but i have my windows up giving less drag.

in fact i got my best highway milage to date(29mpg) running around 75mph with my windows up and a/c on(it was partly cloudy and 85deg. or so)

does anyone think drag from having the windows down will pull your mpg down? it affects 1/4 mile times having them down, why not mpg?

Good points. Add "window tints" to the list.

Right, forgot to mention: the same documentation I had read some time ago also mentionned if ac increases fuel consumption 4% - 8 %. consumption increase would be worse by the drag caused by open windows. Amazing isn'it? This is confirmed by BadKarma99 who experienced worse 1/4 mile results with windows open.