Full tank indicator

[island_Vitz]

How do we know we have a full 42 liters or 11 gallons of fuel?
Is it at the first click of the pump or is it when we actually see it fill to the brim? I've been filling to the first click but I kinda feel like my mileage calculations might be off. :iono:

[WeeYari]

First click is the closest to published fuel capacity.

If you fill to first click every time, and properly divide distance traveled by fuel top up amount, there is no way your calculations can be off. The only variable in the equation would be the sensitivity of the shut off on the gas pumps. That is why for truly accurate calculations it is recommended to, as much as possible, use the same station, same pump whenever filling the tank.

[nookandcrannycar]

How do we know we have a full 42 liters or 11 gallons of fuel?
Is it at the first click of the pump or is it when we actually see it fill to the brim? I've been filling to the first click but I kinda feel like my mileage calculations might be off. :iono:

I've always filled until I can start to see gas in the neck with every car I've ever driven. In the Yaris, this can potentially cause the fuel vapor canister to fail...but judging from posts, this doesn't happen very often (possibly because most members don't 'go past the clicks' as I do :biggrin:). No vapor canister issues re my 2007 Yaris in just over 300,000 miles (from new). I've driven over 1.2 million miles in over 35 years of driving and I've always 'filled till I can see gas in the neck' and have never needed any repairs that were fuel related (I know, anecdotal evidence :biggrin:). I always know that my MPG figures are correct because I have a consistent reference point, AND do miles on tank/gallons on fill-up rather than relying on a car's MPG gauge or computer.

CTScott tested the tank on one of his 2nd Gen hatches for absolute capacity and concluded that absolute is 12.8 gallons. Dead on correct in my book...not only because it was CTScott who measured this :biggrin:, but also from my own experience. I once ran out of gas while pulling into a gas station in my 2007 Yaris, and it took 12.777 gallons until I could see 'gas in the neck'. Very logical that from that point up to 'filling it to the brim' would be 0.023 gallons.

[nookandcrannycar]

First click is the closest to published fuel capacity.

If you fill to first click every time, and properly divide distance traveled by fuel top up amount, there is no way your calculations can be off. The only variable in the equation would be the sensitivity of the shut off on the gas pumps. That is why for truly accurate calculations it is recommended to, as much as possible, use the same station, same pump whenever filling the tank.

There have been some past threads, which IIRC included CTScott weighing in on this, indicating that there are some things that can cause 'the click' to not happen at the same point/place every time.

[island_Vitz]

Thanks for the replies.
I've been using Fuel Buddy app to record and calculate fuel efficiency instead of doing it manually. I'll do it manually as well and compare results. I'll also try my best to fill up at the same station and pump. I have heard before that different pumps can have different sensitivity.
I'm scared of filling to the brim as once with my VW my fuel tank started leaking right after filling to the brim. Maybe there's no connection but I'm scared.

[WeeYari]

There have been some past threads, which IIRC included CTScott weighing in on this, indicating that there are some things that can cause 'the click' to not happen at the same point/place every time.

While true, out of 479 fill-ups with this car, I've only had one instance where the first click shut off was blatantly early. Does shut off occur at exactly the same point every time? Certainly not, but based on my ongoing calculations, the discrepancy between pumps is acceptable for monitoring mpg.

BTW, I really only record mileage for purposes of monitoring condition of the vehicle, not for trying to milk every km/liter out of this thing that I possibly can so small errors in calculations don't phase me.

[island_Vitz]

While true, out of 479 fill-ups with this car, I've only had one instance where the first click shut off was blatantly early. Does shut off occur at exactly the same point every time? Certainly not, but based on my ongoing calculations, the discrepancy between pumps is acceptable for monitoring mpg.

BTW, I really only record mileage for purposes of monitoring condition of the vehicle, not for trying to milk every km/liter out of this thing that I possibly can so small errors in calculations don't phase me.

Okay cool. I work on the road so I have to milk every km/litre :laugh:
Been getting like 25mpg. This job has made me change my driving style and I'm now running my tyres at 41psi

[nookandcrannycar]

trying to milk every km/liter out of this thing that I possibly can

:laugh: Yeah, I must admit I probably do that quite often (miles rather than kilometers of course). I don;t like having to hand over more money than necessary to 'the gas man' :laugh:.

[BLKHILLSGUY]

Thanks for the replies.
I've been using Fuel Buddy app to record and calculate fuel efficiency instead of doing it manually. I'll do it manually as well and compare results. I'll also try my best to fill up at the same station and pump. I have heard before that different pumps can have different sensitivity.
I'm scared of filling to the brim as once with my VW my fuel tank started leaking right after filling to the brim. Maybe there's no connection but I'm scared.

I personally wouldn't recommend it. When the gas dispenser stops, that's good enough for me. I don't want to risk it by overfilling. And from what I've read online, it's not recommended anyway. I personally fuel slowly on the first notch. That's just my style. Kinda sucks in the winter when it's blowing like hell, but I've had the gas nozzle not stop and spill fuel all over my paint and the ground in the winter. So I stand by the gas nozzle and watch the pump. Better to be error on the side of caution.

[nookandcrannycar]

I personally wouldn't recommend it. When the gas dispenser stops, that's good enough for me. I don't want to risk it by overfilling. And from what I've read online, it's not recommended anyway. I personally fuel slowly on the first notch. That's just my style. Kinda sucks in the winter when it's blowing like hell, but I've had the gas nozzle not stop and spill fuel all over my paint and the ground in the winter. So I stand by the gas nozzle and watch the pump. Better to be error on the side of caution.

One thing I have found interesting are the different nozzles in different states and different vintages of gas stations and how that often translates to the general political mindset within that state. Blue States = fairly stiff or very stiff 'collars' that try to keep the consumer from filling up 'unsealed'. Red States = weak collars or no collars at all (CA leans toward the former, TX the latter). I've even seen some old rolling wheel completely non digital pumps with no collars in the last 5 or so years...all in Red States in the South. In the City Profiles section of Moving.com one can search zip code reports for pretty much any zip code in the USA that has residents (compiled by the company Onboard Informatics). Air Quality is one of the measurements within those reports. The national average is 100, and lower is better. My previous county (Marin County, CA) ranges pretty much between 80 to 85. My 'new' county (Montgomery County, TX) also 80 to 85. Incline Village, NV (on Lake Tahoe in the Sierra Nevada mountains) is also in the low 80s range.