Honda is great for thinking their customers are stupid. My mileage went from 40 mpg to 25-28 mpg after a software upgrade last year. I took my 2006 HCH into the dealer last month and had it checked for malfunctions, and of course they found none. They told me they got 40 mpg after driving it 5 miles. After I picked it up, the mileage dropped like a rock back to between 25-28 mpg. which I have experienced since the software upgrade. I wrote their corporate headquarters and got a canned patronizing response from one of their trained customer complaint reps who told me the conclusion was that the degradation in the mileage was due to my "driving habits." My driving habits have not changed and certainly not changed significantly to cause such a severe drop in mileage. I got the same patronizing b.s. when I experienced a defect in their windshield glass. Time to buy a Prius!!

 

Impossible!!!

 

Pro tip, you can get a car manufacturer to fix (almost) anything if you talk to the right person in the Chain of Command. It can be very frustrating to find that person, heck they made it hard to find someone who can help you on purpose, no doubt. The road is byzantine but there is a road if you search hard enough.

Have them do an overnight check of the battery pack or if that dealer wont….take it to another.

 

What region do you line in? If you got it "last year" before a cold winter, possibly the temperature has something to do with it. Did you put pipe insulation in your front grill? Why did you only get 40 mpg before? Do you speed? Did you pump up your tire pressure? Are you done venting? Do you realize your battery will last longer?

Good luck, nf

 

Please re-post in the HCH II specific sub-forum for everyone's benefit, and an improved response to your concern.

 

NF:

Pleeeez! I live in So. Calif. - don't need pipe insulation. I am a very conscientious driver and away of fuel saving driving techniques. It's all about getting 38 mpg for 4 years; having the dealer install new software and then getting 28 mpg.

 

Try this out, on the 15 freeway on that big hill going north before you hit the 76 off ramp make sure you go into the hill with full SOC or 1 bar from it actually is best. Then Drive up the hill in the fast lane at 75+ while in D try to keep the assist gauge about 1/2 way up on the scale. Notice how fast your SoC drops, did you make it to the top of that hill without falling below 3 bars? if not then your battery is suspect IMO

For reference if I do this in my HCH II I will only use up 3 or so bars getting to the to top and still have 1/2 charge or better on my pack. They key to this system working well after your update, is that your battery pack has close to the same Amp Hour rating as a good/newer one. If it doesn't i think the car gets confused and charges way too much which will dramatically lower your FE...

It's also possible your D range isn't working properly on your CVT and even though it says D you are still in S all the time. this is much less likely than a drained/damaged battery pack though. Try shifting back and forth a few times at about 40 mph, is there a noticeable increase in RPM when you drop it to S? or does it feel the same?