Hi NASAgineer:

___The HCH-II increments in .1 mpg decrements then? Finally! Our MDX has .1 mpg increments in the FCD but the Accord’s TC in the NAVI, AH’s TC in the NAVI, Insight, and HCH-I all had the metric conversion based and goofy .3 and .4 mpg increments

___Good Luck

___Wayne R. Gerdes

 

Hello there, Jesse here from Hingham MA. Happy thanksgiving. I just drove to Worcester from Hingham (about 80 miles) with my father in his 2005 infinate ratio HCH. We have about 23,600 miles so far. Driving all highway today with average speed around 70mph and twice hitting 90mph down hill, we got 43mpg. Keep in mind the temperature was only in the upper 30's fahrenheit. When we bought the car back on 10/29/05, we did a 10mile test drive round trip highway at 60mph. The temp was 50 deg and we got 50mpg with all three of us including the salesguy on board. The car was brand new with 2 miles on it. Maybe you are driving way too fast. I only get mid 30's when I drive over 90mph. Also short trips kill mileage as well since cars burn more fuel when the engine is cold. Plus autostop won't work till the engine has warmed up. During the warm weather cruising around town at 35mph, I can get 70mpg. My advice is to do a round trip test (to cancel out hills and wind etc) at 60mph and see what happens. If you do not get 50mpg or more, I would bring the car back, demand a refund and tell the dealer to %&$& it self and buy either a prius or an hch from another dealer. By the way my prius now has 201,600 miles and counting and easily meets or beats epa and runs like new. Good luck. You can email me with any questions at seenuinoz@hotmail.com.

 

Hi Geophrey,
So far, I have about 8000 miles on my HCH. What I notice most is that when I first fill the tank I can typically get very high MPG's, something like high 50's low 60's for about the first 40-50 miles then it starts to decline into the more typical range that I generally have been averaging, (high 40's cold weather and low-mid 50's in warm weather). I've never had mpg's fluctuate from low to high by large amounts.

After averaging many tanks over 8k miles, my mpg gauge display at fill up is very close to the calculated mpg's. Now, I only see a slight variation, maybe 0.2 to 0.5 mpg's. In the beginning there was a bigger variation. Therefore, more data points = better results.

When filling up, I don't top-off and I think this will make a difference as well.

Best of luck,
Ralph

 

Yep, I managed to inch mine up from 47.7 to 47.8 right before my first fillup.

 

Thanks for everyone’s interest.

In response to filling up: I was previously always going to a shell station (do not have Hess on the west coast) and always letting the pump shut itself off. I thought that would standardize fill ups, as much as possible, but from reading other posts I appear to be in error. From now on out, I will top it off with as much gas as possible.

When it comes to fluctuating tank mpg: The 06 measures mpg by .1 of a mpg, which I was assuming, would make it very accurate and function similar to how other hybrid owners have described their cars. However, I still feel (I do not have the mathematical or technical know how to back it up) that my tank mpg changes to easily after a few hundred miles. I can drive ~15 or 20 miles and see the tank mpg fluctuating up or down a handful of mpg even after a couple of hundred miles on a tank.

In addition, while I have your attention, has any other 06 owner noticed a similar real time mpg gauge problem? Is it even a problem or is it just “calibrating” itself? Ralph_dog thought it could be a NO2 purge. Any other ideas?

 

Geophrey,

I'd be cautious about "toping it off with as much gas as possible". There are a number of hazards you risk with this practice, and it's environmentally less desirable. I'm going off what others have said about this. I personally let it fill until it clicks off once and call it good. Yes, there may be an error margin but it (in my mind) beats the risks of overfilling.

In my 03, I've observed an average error margin of -3.1 MPG from the display to the actual (the display has always been higher than actual - this is over 82 tanks of gas). I know the 06 is different in many ways, but we won't know if the 06 display performs better for a while.

The fact that you get large variation at the end of the tank (400+ miles) is odd. I suppose I can only say this is contradictory to how the 03-05s perform - mileage stabalizes greatly as the tank wears on. At the 400 mile mark, I'm lucky if I can push the mileage +/- .3 in either direction.

 

The HAH's dash/FCD display is quantized to 0.1mpg.

 

Hi GoNavy:

___Unfortunately, the AH’s NAVI is not

___Good Luck

___Wayne R. Gerdes