I have finished my 1800 mile trip. I used 3 tanks of gas to travel from Boston to Miami. Not too shabby. On the trip, I averaged around 39mpg, which is somewhat disappointing. The first leg, I did not use the AC and was able to attain over 43MPG, very nice indeed. The second two tanks I've used the A/C, and MPG has declined to around 37-38mpg. I also had to drive faster in the south than in the megalopolis of the NE, where 55-65 was more common than the 70-80 in the south.

I saw only two TCH's on the entire trip, both in northern Virginia. One was Jasper Pearl and the other was red.

 

You have to include the cycling of the compressor it's not static, which the computer controls. But from my short drive without AC about 50 miles since I have the TOH, I would think no more than 5 % less mpg with AC on.

 

Did you mean to say that "39 MPG highway is somewhat disappointing?"

That's above the EPA rating for highway. If you can get 39 MPG for every highway trip you take, it would be hard to understand your thinking of that as not good enough.

The TCH is not a Prius or an HCH. To get 39 MPG out of a car this size is quite a technological feat if you ask me.

 

39mpg running the A/C and going between 70 and 80mph is excellent. I get about 41mpg with the A/C doing 60 to 65mph, and about 44mpg without the A/C.

 

I could get 35mpg in my 03 Accord with the A/C on...so a 4mpg increase is not that great. Keep in mind the tires were also inflated to 38psi Cold.

Yes, it's over 38mpg, but on the other hand it's very hard to get 40mpg in the city. Especially with A/C use.