Yea my hand calculations are relatively close too. They have just been going up due to the weather warming up and my diving habits getting better.

The overall difference between the MFD and hand calcs is relatively minimal.

 

I think a main part of the difference is where the MFD thinks the top of fuel level is in the tank. I have noticed that the MFD often starts with optomistic FE and range calculations and these seem to approach reality (hand calculations) as the quantity in the tank decreases. IMHO it averages the miles travelled from the small amount of fuel top-off above what it thinks is the maximum usable fuel quantity into the "total miles since filled". Since the top off mileage is small and a constant, it has less effect on the overall FE calcualtion as the distance travlled gets larger and the fuel remaining gets smaller.

 

My range calculations are always off by a good amount. Whenever I fill up and do the reset they are always under 600 miles and I know for a fact that I get better than 34.8 miles per gallon. Has anyone ever had it report a Range of more than 600 after they fill up?

 

I think the cruising range may not update right if you overfill. It wasn't until I started stopping at the second auto-stop that it really started going up. Of course it's just starting to warm up again now so not sure my cruising range has recovered, and don't remember what I got last year, but I believe one of the top mileage people may have gotten 700+ cruising range at some point. I have a vague memory of a photo posted... Okay yeah here: https://www.greenhybrid.com/discuss/...tml#post141972

 

Yea I remember that post. I don't over fill. I don't go past the second click.

 

Yes. I routinely see 650 to 670 miles on the range. The key is to get higher MPG. Nash has reported having 700+ on his range.

 

My range comes up at 512 miles. I am getting about 34 MPG, but this week I have been happy seeing 37 (warmer outside).

I live in the SF Bay area. Lots of freeway driving (90 miles/day) but the bay area freeways have a lot of up/down hills which really kill the MPG.

 

My last tank was 41.5 calculated by hand. The current tank with 1\4 tank left is 42.6 per MFD. I don't think I am going to get much higher than that. Even at 41.5 I should be able to get 700 miles on the tank. The range should easily read over 600 miles and it never does. I know in my signature it says that my Lifetime AVG MPG is 36.8 but, not that it makes much of a difference, my Lifetime AVG per my records is 38.6. Even using an avg of 38.6 theoretically the tank should get 663 miles. The range reading should still be over 600. Heck with 1\4 tank left right now it is reading less than 90 miles. Let's say the guess gauge is close to being accurate. 1\4 tank holds 4.3 gallons. Let's say that the MFD is really off and I am only averaging 40mpg right now. With 1\4 tank left I should still get 172 miles until the tank is dry with fuel left in the line......if the tank is truly filled up all the way to start. Let's take off 25% for error purposes, which is way more than generous, that would leave me a range of 129. This is still way off.

Not that I trust the RANGE calculations of the vehicle but if you're going to have something like that on there shouldn't it be relatively close to being accurate? BTW since you can't tell a person's tone over the internet I am not angry just debating.

As extra info. I usually fill up no later than when the warning light comes on and I never get in more than 14 gallons. Shows how inaccurate the gas gauge is.

 

I think the range is for 'regular' people, those that just drive the car and want to know (generally) when it's time to fill up again.
I don't think it was designed for 'gamers' who are trying to eek out the ulitmate tank of gas (800 miles) or to see how exact the system is.
It's a general point of reference, not a precise statistical measure.

I think the car can only guess how much fuel is in the tank (as it sloshes around), thus the inaccuracies.

IMHO

 

I would have to agree with that to a point.

If the car is sitting still when you fill it up shouldn't it be able to get a pretty accurate level of fuel during the initial calculation?

You would think that since the car calculates higher for the MPG that it would calculate higher for the range too. It's kind of odd that the two go in opposite directions.

I would have to say that I am the later of the two types mentioned as I don't try and squeeze out the last drop of gas. Personally I want to be able to go as long as I can on a tank of gas so I can save money. My car is Money savings first and environment second for me. Don't get me wrong I do care about the environment as I have made other changes in my home. You can't expect someone to change a whole way of life or thought process overnight.