Topping of fuel tank may leave 2 gallons below max fuel capacity

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I saw a dude topping up his newer 4 runner the other day at sams club.
Like 20 extra clicks. No exaggeration.

I saw a predelivery tech for the local Ram dealer do the same the other day. Absolutely brand née truck, clicked it at least 15 times. Shaking me head.
 
That’s pretty bad. My worst example was watching someone top off until fuel came out of the filler neck on a late model Kia.

I think for some people it might just be OCD. Others just don't know any better or think they're somehow putting one over on the man by getting every last drop of gasoline into the tank.

I was driving my Disco 2 that day and the dude was giving off serious bro vibes, so I just sat back and watched. If it had been someone approachable or I was driving one of my nice, old Toyotas, I might have attempted an intervention. :)
 
I saw a guy topping off his Prius at the gas station until fuel spilled out onto his foot. He was wearing open toed flip-flops. :slap:
Birkenstocks?
 
This thread reminded me of an instance several years ago. I was driving from St. George to Portland and stopped for gas. I was filling up at a Costco gas station and the pump stopped after around 15 gallons. I knew that couldn’t be full since I had driven 300+ miles in the cruiser so I started the nozzle again. Next thing I know there is gas overflowing from somewhere underneath the car (not out of the fill receptacle). Apparently the auto shut off was not working and allowed more than 24 gallons and I couldn’t figure out why it wasn’t overflowing from the nozzle. Guess I now know where it was going 🤣
 
Is this a fill up from the computer showing near or zero miles to empty?

There is about 2 gallon of reserve gasoline which is past the zero miles to empty on our 200’s and probably the way it is done on all Toyota’s. This results in having about 21 to 22 gallon of fill up’s from “empty”.

Checking back it maybe more like 3 to 4 gallon of reserve fuel. See other thread about this.

I know that the reserve on my 80 & 200 is generous/conservative. When the light goes on, I've got more than 3 gallons.
How far will 3 gallons Take me?:meh:
How long is a piece of string?
 
I know that the reserve on my 80 & 200 is generous/conservative. When the light goes on, I've got more than 3 gallons.
How far will 3 gallons Take me?:meh:
How long is a piece of string?
Yep. I also fuel up before indicated “empty”. It does mean refills are usually around 18 to 20 gallons.
 
I know that the reserve on my 80 & 200 is generous/conservative. When the light goes on, I've got more than 3 gallons.
How far will 3 gallons Take me?:meh:
How long is a piece of string?
Yep, mine is 4Gal or so.
 
I’ve NEVER had mine stop filling 2 gallons before it was full. Maybe a quarter gallon if I top it off.
 
Yep, mine is 4Gal or so.
Agree, mine has very consistently been 4 gallons. I don’t care to admit how many times I’ve run my tank well below the light in the 6 months I’ve owned mine
 
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Accidentally topped off when towing.
Birkenstocks?
Hey now, don't be coming after my Birkenstocks. Just towed my camper over 1,700 miles in the comfort of my beloved birks.

And to the point of this thread, I definitely did not top off the tank. I accidentally topped off my tank when towing my camper to Big Bend area last year. It was the first and last time I ever saw fuel vapor coming out of the gas cap.
 
Accidentally topped off when towing.

Hey now, don't be coming after my Birkenstocks. Just towed my camper over 1,700 miles in the comfort of my beloved birks.

And to the point of this thread, I definitely did not top off the tank. I accidentally topped off my tank when towing my camper to Big Bend area last year. It was the first and last time I ever saw fuel vapor coming out of the gas cap.
Hopefully completed the look with calf height wool socks! If not, there’s always next time.

To beat the dead horse further, do not top off your tank. This will lead to a host of EVAP CEL’s.

IME, P2420 is the code that indicates your charcoal canister is dead. It’s a $4-500 part that’s tucked away nicely. Not something you want to have to deal with again and again.
 
Hopefully completed the look with calf height wool socks! If not, there’s always next time.

To beat the dead horse further, do not top off your tank. This will lead to a host of EVAP CEL’s.

IME, P2420 is the code that indicates your charcoal canister is dead. It’s a $4-500 part that’s tucked away nicely. Not something you want to have to deal with again and again.
The maddening part is that it is likely just a $20 VSV in the canister that dies when it tries to switch liquid rather than vacuum. In my case (2002 Sequoia) the VSV wasn't available separately from the canister though it is available for some other models.
 
When topping off fuel at a gas station, the fuel dispenser automatically stops when the fuel tank is full. The stopping mechanism works mechanically via venturi effect through a small additional opening in the nozzle, that starts sucking in fuel when the tank is full and thus stopping the fuel flow automatically. However, the fuel also causes foaming and the foam can have the same effect and shutting off the fuel dispenser. In all occurrences where the fuel dispenser stopped automatically, I was able to add more than two additional gallons of fuel until the tank was really full, by pulling the nozzle out and letting the fuel flow at a lower rate.
Two additional gallons is almost 10% (24.5 gal capacity for 200series), which is more than I expected. That additional 10% can be useful when optimizing for range, say when pulling a trailer and gas stations are spaced far apart, or one refuels at a very cheap gas station.

I can get 2.5 - 3 gallons more after auto shutoff. Of all my vehicles, LC200 is the worst for shutting off early.
 
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After I fill up my scanguage reads ~24 gallons. The low fuel light comes on around ~4 gallons. This is very consistent by the way.
 
Until I owned this LC, I would often fuel beyond the first or second click.

I wonder if this habit is what ruined my charcoal canister (though I’m not sure it wasn’t my misuse of the LRA aux tank pump).

But I do find it interesting that all of my past post-click pumping never caused an issue… that I know of.
Did I just get lucky or is the issue limited to our vehicles?
 
Before my 200, I too topped off. I however thankfully read a lot of posts, watched ccn, and heard about this before I got into the 200 seat for the first time.

I have never topped off or gone beyond one click given others’ experience and am still having these issues.

@Umbrarian do the pumps you are able to get 2+ gallons from belong to the same station? Or is this regardless of fill location? In any event, I’d stop doing it. But it’s your truck.
 
After I fill up my scanguage reads ~24 gallons. The low fuel light comes on around ~4 gallons. This is very consistent by the way.

Only time I drove it till fuel light came on it said 3 miles to go, I chickened out and as I was pulling into station it went on. I then put 23.56 gallons in.
 
@Umbrarian do the pumps you are able to get 2+ gallons from belong to the same station? Or is this regardless of fill location? In any event, I’d stop doing it. But it’s your truck.

It was any station that has a high fuel flow rate from the pump. I found when it was a slow pump, it filled up correctly. Seems the high flow rate has blowback and prematurely activates the shutoff. Some places are so high it kicks off after I only put in a few gallons, when I know it needs 15+. I figured it is the anti-siphon block that cant process fuel fast as it is coming in. So now I just fuel at the lowest fuel flow setting and do not top off and I have a full tank.

eta

I guess what I am saying is if you can get several more gallons in, try running the pump at a slower flow rate.

eta2

I discovered this because I was tracking mpg manually, and it was higher than trip computer, so I knew I was not getting a full tank.
 
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I can get 2.5 - 3 gallons more after auto shutoff. Of all my vehicles, LC200 is the worst for shutting off early.
I think we should setup a competition who can top off most and report back. That would be about right for those still wanting to do this…
 
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