Disappointed with Civic Hybrid mileage

The car’s freeway mileage is fine (48-50 mpg in Los Angeles), but with the AC on, I’m only getting 25 mpg in city driving in my 2008 Hybrid. Granted it’s 92 degrees out, but I put in ‘good’ gas and keep the AC at 73.

Anyone have any ideas of why the mileage is so terrible?

I don’t know if running the AC is part of the federal mpg ratings methods. My guess is you are parking and exiting the car and coming back to it several times a day. Are you in a sales job, so perhaps you are sitting in the car making notes with the motor running and the AC on?

AC compressors are a strong drain on a small motor. I think the Civic hybrid drives the AC off the gas motor in a similar set up as a conventional motor. When you run the AC the gas motor must run and that uses gas.

For your next car you might do better with a Toyota hybrid. Toyota drives the AC with an electric motor on some of their hybrids. This means you can “keep your cool” with the AC on and it is running on battery power.

The gas engine is always running, never in the ‘sleep’ / battery only mode. Hence the resulting mpg relative to that.
For the same number of miles driven with out a/c, compare how often the gas engine is running and at what rpms.

The Ford Escape hybrid has a choice of a/c settings. Two of which allow the engine to sleep, at which time the a/c air warms up until the next engine rpms turn the compressor.
Does the civic give you this option ?

Do you coast up to a red light or get heavy on the brakes at the last moment? I know it is hard, but try the windows down option. At least LA is relatively close to the ocean

I’m not sure about the Civic hybrid, but most car A/C units can draw up to 35 HP on start up and around 10 - 15 HP steady state. For a 300 HP V8, this will have a smaller effect on fuel mileage than on your four-cylinder Civic. There’s no magic formula to improve your mileage. Parking in the shade rather than full sun will help. White or silver cars are better than black. Use a windshield sun reflector. Are your tires relatively new and properly inflated? Drive only at night. Install sheepskin seat covers (they wick moisture from you clothes and skin). Goggle “hypermiling”.


How are you measuring that mileage? Are you looking at an onboard readout? or are you dividing the number of miles by the actural gallons consumed?

What do you mean you put in ‘good’ gas? I hope you aren’t wasting money by buying gas with a higher octane reading than the car needs.

I would like to know how you are measuring fuel economy. Your methods might be part of the problem.

“At least LA is relatively close to the ocean”

You don’t have to get too far away from the ocean for the temperature to shoot up. Downtown LA is far enough away that the ocean has little influence on temperature. Real temperature moderation is only in the beach communities. If you are east of the 405, it can get really hot. That’s just LAX and about 5 blocks from the ocean.

Thanks for responding. I am looking at the onboard readout, but I am also calculating the mpg via the miles driven and gas used. That figure comes out only about 1 mpg higher.
I took it to the dealer but they say nothing is wrong and hinted that it was my driving habits. I haven’t been driving it any differently than when I got 39 mpg.

Thanks for your response. By ‘good’ gas, I mean Mobil/Exxon etc not Valero or ARCO. I am using the onboard monitor AND my own calculations to measure fuel economy. They are usually only about 1 mpg off.
I took the car to the dealer and they said nothing was wrong and hinted that it was my driving that effected a huge drop in fuel economy. I said I was not driving it any differently than before. I think they are trying to pull one over my eyes.

“By ‘good’ gas, I mean Mobil/Exxon etc not Valero or ARCO”

Valero is actually the largest refiner in the country at this point, and they supply gas to all of the other gasoline companies.

While nobody ever really knows the exact origin of the gas that they are using at any given point, I can guarantee that you have used Valero gas on many occasions, even though it came from an Exxon or Mobil pump. What does vary somewhat from brand to brand, however, is the detergent additive “package” that is added to the gas at a retailer’s distribution terminal.

That being said, there is nothing spectacular about the additive package used by Exxon or Mobil.
If you are seeking a superior level of detergents, you should use a brand that is one of the “Top Tier” brands advocated by Toyota, BMW, Honda, GM, and VW. In my area, that would be Shell. In your area, you might want to try Chevron. However, despite the superior detergent additive package in these two brands (and in other Top Tier brands), you are still likely to be using Valero-produced gas on some occasions, at least.

The only way to really measure this effect is to do some city driving with the AC off.
With fall coming this should not be a great burden.
If you get in the car and it’s hotter inside then drive awhile with the windows open.
That’s more efficient than going right to the AC.