My 1 1/2 yrs. of experience with my 06 Civic is I can get very high mileage in continuous driving (40 to 50+) if I keep the speed at 65 or under, accelerate slowly and smoothly, and coast on the downhills. Lots of start stop driving will lower the mileage to the low to high 30s. I have upped the tire pressure to around 40 but I don't find that results in much of a gain in fuel efficiency. Cold weather cuts the fuel economy and I suggest partially blocking the intake and using an engine block heater.

I would check with the dealer to make sure that you have the most up to date firmware for the cvt and it is working correctly. I had my dealer update the firmware and my ride is smoother and I think the fuel economy is slightly better.

Good luck

 

Thanks, dhill. My 08 Civic Hybrid mileage has improved from around 41 MPG to nearly 44 in mixed driving. I increased the tire pressure and it is summer now so the engine probably runs more efficiently. Also, there may be something to the notion that a car's engine efficiency improves as it gets "broken in". What do you think?

By the way, what is firmware?

Thanks.

 

Hi Johnny,
I can't speak to whether efficiency improves after the engine breaks in. My understanding is that it doesn't take much time to break in modern car engines but the Civic may indeed get better mileage after driving it for a while. I also believe that mileage improves as the tires get broken in.

As to your question of firmware, my understanding is the Civic has software that controls the cvt and the charging and discharging of the battery. Honda issues updates to this software that your dealer can download to your Civic.

Derek

 

37 mpg is exactly what CR rates the HCH in terms of overall mileage. See http://www.consumerreports.org/cro/c...ient-cars-206/.

The IMA system in Honda hybrids is TOTALLY different than Hybrid Synergy Drive in Toyota/Lexus hybrids. The IMA system has no power split device and only 1 motor/generator vs. 2.

See http://www2.toyota.co.jp/en/tech/environment/ths2/. HSD is a series/parallel design whereas IMA is parallel only. Also see http://eahart.com/prius/psd/ and http://prius.ecrostech.com/original/PriusFrames.htm (under Understanding the Prius) and http://world.honda.com/automobile-technology/IMA/ima02/ (Honda calls series/parallel hybrids combined instead).

Your HiHy should have a system similar to the above but the RPM limits and ratios will almost certainly be different. If it's 4WD/AWD, I'm not familiar w/changes they had to make to accomodate that.

 

In short drives ( under 4 miles ) in hot ( over 80 degrees ) 37 is about right. The computers in the HCH II will not allow the batteries to discharge if the temperature is too high inside the civic. On longer drives (over 20 miles ) at interstate speed ( doing 70 mph with cruse control ) I get 50 mpg. I have the tires pressure set to 40 psi in all 4 wheels. in 11,800 miles my average MPG is 44.6. I have had tanks of over 50 driving from NW Arkansas to Central North Carolina and back. When we had Ice and Snow on the roads, I only got 35 mpg on a tank.

The EPA estimate of 41 MPG may be right. Hot weather and short drive do kill the mileage in the HCH II. Longer drives do get the mileage up.

There are tips on how the HCH II computers ( firmware is programs the computers run ) decide how to use the batteries and when autostop will be allowed. If you follow those tips, You will get better mileage, some of the tips apply to any car, hybrid on not.

 

I have the perfect commute for my 2009 HCH.
Had the car for just over a month and average 65-70 MPG (Imperial) that is just over 50-52 MPG US I believe. (4.0-4.3 L per 100 kms)
I have a bit of hwy mixed in with rolling hills where I can get good glides going. My commute is 40km each way, a bit of bumper to bumper.

I believe you have to have the right conditions to maximize economy in any car, short drives under 10 miles kill economy.