Great job Chris. Start entering it into the Hybrid Milage Database!

 

I know it's been mentioned here before, but the onboard MPG calculations are pessimistic. On tank # 2 it said I got 43.7 mpg when in fact I got 47.4

 

They are sometimes lower and sometimes higher. From my experience, they are usually lower.

 

I believe there will be error whether we use the onboard MPG or do a manual calculations. For manual calculation, there could be air trapped in the fuel tank that reduce the amount of gas that we could top up. This will eventually give us a higher MPG as we see lesser gas used for a given distance.

 

It makes sense, but as I think about it....5% of a 12 gallon tank is a little over 1/2 a gallon of air. Or maybe I'm thinking of it the wrong way. Either way it appears I have the basic technique down and am very pleased with the mileage I'm getting.

 

These comments above are real life conditions. Today I inflated my tires to 44 PSI to see what this change would offer. I traveled 82 miles on 95% freeway travel in light traffic. I set the cruise control to 65 MPH and used manual throttle when needed. I averaged 48.1 MPG using the in car gauge. My previous best is 40.1 MPG before I set the tire pressure. Not apples to apples as this was done over a much longer range (400 miles), speed was 75+ MPH and it was my first tank on a new to me 07 HCH II, tire pressure 36 PSI.

Setting the tires to 44 PSI makes for a harsher ride, but subjective opinion, car seemed to roll easier and took less power to achieve the same performance.

There are many factors that affect MPG; some in our control and some not. I do think however, given a 6 year experience with a 02 Accord 4 cyl at 28 MPG lifetime, the HCH II does return some very impressive MPG.

TDSOUP

 

a 5% error can give a 3 MPG difference in reading.

 

You forgot at least one factor:

8) Inconsiderate spouse that drives your HCHII like it was a dragster because they don't care about the mpg (When my wife is on Empty in her 17mpg Honda Pilot, she takes my HCHII instead of taking her car to the corner station!)

My wife took the car 30 miles (mostly freeway) and dropped the mpg from my record 49mpg for this winter so far (after 120 miles on the tank at that point), down to 42mpg! Now I could see if had 20, even 40 miles on the tank at the time that the mpg could fluctuate easily by 7mpg with her driving... but at 120 miles she was able to destroy the tank mpg! I was pissed, and truly noticed how badly she drove when I could barely squeeze 500 miles out of that tank. I was never able to recover as the weather got worse with lots of rain and colder mornings (30's). After tank calculations I got about 43 mpg! I know it's sad to say that I'm pissed with 43mpg... but after the great start I had, I thought I would pull a 600 mile tank for the winter!

 

Sounds to me like the answer to your problems would be to trade that gas guzzler in for a more efficient car- maybe even another hybrid. That way, her tank wouldn't be empty very often and she'd leave your car alone!

Alternatively, you could teach her to drive more efficiently. Some people are receptive to it, even in non-hybrids, you know. A few tips and you could be on your way to a new marital harmony.

 

Just came back from a trip to Kingman, about 2500 miles round trip. got 48-49 MPG mosdt of the trip, but on the return trip, decoded I wanted home in one day, so I dialed in 75 MPH in AZ/NM, and 80 MPH in west Texas, just slowing down where speed limits were lower. Lordsburg fillup gave me 49 MPG, the Fort Stockton fillup 48 MPG. Didn't fillup here yet, but the car indicated 41 MPG which equates to about 43 MPG at the pump. Had pretty heavy headwinds last 200 miles, which accounted for the decrease. Is this car great, or what!