Automatic climate control and MPG

[djminfll]

I don't know why it took me this long to consider this, but I started keeping the A/C on 72F and the fan on the lowest setting, instead of using the Automatic Climate control. My last fill-up was at 49.1mpg, and my current tankful with 300+miles is sitting at 48.4mpg. Does using the automatic climate control really effect fuel economy that much? In the past two weeks, my lifetime average (reset at 40K miles, I currently have 51K) has gone from 44.7 to 45.2. I was pretty happy with my average of 44.5mpg, but if I can squeeze the extra 4-5mpg just by keeping the A/C blowing a little more gently, I can deal with the car being a little bit warmer for a little bit longer.

Has anyone else found similar comparison figures?

[Cobra348]

Hadn't tried that TBH. I've been using A/C to cool the cabin with the seats on cool as well. Once the cabin is reasonably cool, I shut off the A/C and only go with the seat cooler. Frankly I'd rather have the cabin generally cool as well. I'll give your idea a try.

[Waldo]

Yes, A/C will make a big change in your MPG number, but when you actually calculate how many gallons of fuel the difference really is, you'll find it's not as big a deal as it seems.

[jadei]

I keep my climate control on auto almost all the time. Sometimes when I want to cool down a minute I hit max a/c then cycle back to auto again once I'm cool. When you first start a hot car it won't blow very hard on auto until 10+ seconds then it will ramp up so don't hit max a/c too soon. You can watch the Kw used in your Myview gauge (if you have it set to show the climate and accessories power draw.) Once the interior is cooled to the set temp it ramps down the A/C compressor.

 

Another marvel of engineering...that variable speed A/C compressor.