Hi,

I am not sure if I should enter my 1st tank into the database, as the values is definitely not accurate.

I receive the car with a half filled tank. So, on the 1st top up, my mpg is . Since the mileage travelled is very low, and yet I need to top up more than half a tank.

What is the practise here? Should I just remove my 1st tank, and make my 2nd tank the 1st?

 

Personally, I wouldn't mind but when I asked the same question back in January, the concensus was the first tank was important data and should be kept. In my case, it delayed hypermiler status by two weeks but I still think there should be "first tank forgiveness."

Bob Wilson

 

I just thought the data will be more acuurate if everyone 'started' with a car that is with a full tank. I dunno about other countries, but I just have to dive a few miles from the dealer to get my tank top up full. My 2nd fill up will actually shows how much fuel I used for the initial run in. The 1st fill-up only show how little fuel my dealer gave me when I collected the car... :-(

 

Ahhh, my first fill-up was a top-off from the dealer and I never thought of recording that MPG. You're right, just drop the first fill-up and keep your mileage.

Bob Wilson

 

Ah... ok. I will re-adjust my data later and kiv the 1st tank... it should be around 30+mpg instead of 1.6 mpg. :-)

I just feel so strange... for one moment I thought I drive a tank..

 

LOL! Perhaps the dealer had hired an ex-tank driver to move the cars around.<GRINS>

GOOD LUCK!

Bob Wilson

 

On the window sticker, I thought it said that a full tank of gas is complementary. Your dealer was cheap or forgetful.

 

Mr. Kite,


I included my first tank data even though there was a large difference between MFD (53.5) and hand calculated (45.5) mpg values. The dealer topped off the car before I took delivery and may not have filled it like I did after I drove my first tank; hence what I think accounts for the large difference in numbers above.

I am only on my second tank and things are much better so far. 65.8 mpg over 530 miles.

You should scrap the first tank values and start with tank #2 for the database as it would be an educated guess for your first tank based on your fill-up. You could use MFD data instead? There are many arguments for and against this.

Thanks,

Chris

 

Every situation is different. If you drive off the lot with a half tank of gas, I would think driving to the nearest gas station, filling up, and resetting the trip odometer is a perfect solution. There is no need to count that fillup as a tank.

I was pretty confident with my first tank numbers. I drove of the lot with what appeared to be a full tank of gas and a total of 5 miles on the odometer. I'm sure the tank was filled up at less than the 5 miles. This would mean that I got a few "free" miles. With my first fill-up, the dash showed FE of 46.1mpg and I calculated 47.6mpg. Over several tanks, my dash has averaged 1.9% lower than what I calculate. I see no reason to not include the first tank--except it would delete one of my "learning" tanks and increase my average.

As for the Prius, it is equipped with a bladder-style gas tank. I have friends with these and large tank-to-tank variations in the calculated (relative to the MFD) fuel economy are to be expected.

 

Consider yourself lucky then, to live near a dealer than gives you a full tank.

I paid a premium for my car (about USD50k) due to the mark ups and taxes, and yet I don't even get as long warranty for my NiHms as what is offered in USA. My last car had just 1/8 tank when I got it. It is a norm over this part of the world.