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how much gas at 0 miles to empty?

Stkid93

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#1
does anyone know how much fuel the fist has left once it hits 0 miles to empty?

i know the gas light comes on once it hits 50 miles to empty. They say most cars will go 60 miles after hitting 0 miles to empty. but the fist has a small gas tank to start with. and when filling up. it seems the fist has closer to 1/2-3/4 left once it hits 0 miles to empty. but I'm not positive on this. if it is only 1/2 gallon that isn't very much. so I'm hoping its a little more than that. i may have to run it down to 0 miles to empty and fill it up to be sure.
 


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Stkid93

Stkid93

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Thread Starter #4
@Mega ST

so that would mean it has at least 1.5 gallons after it hits 0 miles to empty. Interesting I thought it was far less than that. Although there was a couple Times when I was on 0 miles to empty and put a half gallon in just so see and it still said 0 miles to empty. So maybe it’s closer to 3/4-1 gallon. I’ll have to experiment more cause now I’m super curious
 


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#5
There's a few factors that can distort that. If you were driving aggressively for most of the tank. The refuel light will come on sooner based on your higher fuel consumption rate dropping you to zero quicker with more fuel in the tank again based on fuel consumption rate. Then you baby it and fuel consumption improves leaving you more reserve. If that makes any sense. That's how it was in my case any way. If you drive soft with a higher MPG estimate all the way to 0, then drive aggressively after zero, you will probably have less fuel since the computer assumes you will get XX milage based on previous driving habits for that tank. Not sure I explained that the best.
 


gtx3076

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#8
@Mega ST

so that would mean it has at least 1.5 gallons after it hits 0 miles to empty. Interesting I thought it was far less than that. Although there was a couple Times when I was on 0 miles to empty and put a half gallon in just so see and it still said 0 miles to empty. So maybe it’s closer to 3/4-1 gallon. I’ll have to experiment more cause now I’m super curious
Running it that low is stupid. Why would you do that.
 


TyphoonFiST

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#9
Running it that low is stupid. Why would you do that.
Have you noticed all the posts that can be answered with the search thread? [drummer] I vote that he starves his LPFP AND HPFP just to see the side effects* Just like Johnny Cash said...If you're gonna be dumb...you gotta be tough.[driving]
 


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Stkid93

Stkid93

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Thread Starter #10
I see what you guys are saying. But it’s not like the car is being run completely out of fuel. I would think Ford needs to make the car so that it’s able to run on 0 miles to empty because millions of people do that.
 


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#11
All they're saying is you can, but it's not smart. You don't want to starve the pump or potentially clog an injector with the crap that accumulates in the bottom of the tank. I try to fill up before the 25mile mark, and that's only because it makes it easier to get close to the the same E mix.
 


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#12
I see what you guys are saying. But it’s not like the car is being run completely out of fuel. I would think Ford needs to make the car so that it’s able to run on 0 miles to empty because millions of people do that.
Hey Stkid93, I understand the sentiment about "millions of people do it" but as time goes on the consequences of these actions change.
Back in the days of carbureted vehicles, aside from wide open throttle lean conditions due to lack of fuel, and picking up sediment from the fuel tank clogging jets in the carb the consequences of running a vehicle completely out of fuel were fairly minimal...

as time has gone on into port injection the system runs at ~50PSI with there only being a pump in the tank, you now run the risk of clogging fuel injectors, which is still not ideal but repairable at a higher cost if replacement was necessary, and quite annoying.

In the modern age of direct injection with High Pressure Fuel Pumps (HPFP being cam driven in the engine) running at 2000PSI, the pump itself used the fuel as a lubricant and the tank LPFP at ~50psi. when the system is run dry you now no longer have any slipper substance between the metal components in the HPFP and damage "can" occur. It's not guaranteed, but possible.

Depending on the time of the year, in cold weather as the tank gets lower the % water in the gasoline/ethanol mix increases lowering the fuel quality and possible fuel related faults increase, in the summer in an older vehicle there is still the risk of sediment in the fuel getting pulled into the pickup and making it past the pump sock.

In most diesel vehicles running out of fuel is a service call to get the fuel system purged of air, this is $$$ to have a service vehicle come out and assist in the process (newer systems can self prime) and its REALLY hard on the HPFP as it runs at 30,000PSI and is much more prone to accidental damage at that pressure.

I ask the question, why risk it? what does it save? you still have to stop at the pump and fill up at the end of the day, why not do with when there is 50 miles in the tank vs 0? Aside from a trip across the desert and miss-timing a fuel stop in the middle of nowhere, I'd just stop 30-60 minutes sooner than try to push the vehicle to the absolute limit and risk accidental damage to something totally preventable as well as the headache of needing a ride to the gas station to get a can of fuel...

In the end it's your call to make, but there are non-zero risks to running a vehicle fully out of fuel and knowing the difference between having 20miles and 10 miles after the indicator says 0 miles is not super helpful when in reality the vehicle is saying "I NEED GAS NOW" at 0.
 


Zormecteon

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#13
IIRC the light comes on at 5 litres remaining. ... That's not the same thing as when the expected range says 0.
 


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Stkid93

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Thread Starter #14
@sonicmn

I should say running the fuel that low isn’t something I normally do. I usually fill up once the gas light comes on, usually around 30-50 miles to empty.

i am only Interested in knowing this because I run e30 and so I’m curious how many miles you have after hitting 0 in case there’s limited ethanol around. Yes, I can always change the tune to pump gas as well but it’s really just a curiosity thing in case I ever get stuck in a situation where I need to know.

in any case you all make good points and my curiosity does not outweigh the risks. So this is something I won’t be trying.
 


rallytaff

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#15
Sometimes I fill up when half empty. I've only let it go as low as 1/4 full one time. In my 56yrs of driving, I have NEVER run out of gas!
 


gtx3076

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#16
I use tune pluses ethanol calculator to fill up whenever I see fit using the fuel remaining gauge.
 


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#17
I have ran for about 40 miles past 0 before on 91 Oct, city driving, stock car; I refilled with 12.2 gallons. Usually about 11 gallons when just about to hit zero. I can't do that with my new set up, happy feet will take about a quarter of tank in about 50 miles on E50.
 


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#18
Those miles to empty are just an estimate and they are influenced by how you drive. I had one time when I ran the car down to 8 miles to empty and it took 12.4 miles to fill the tank. Since then once it gets to 40 miles to empty I start looking for fuel.
 


D1JL

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#19
I hope you realize that gas in the tank is used to cool the fuel pump.
So, it is not recommended to run a car to empty as it will shorten the life of the pump.
However, it is your car so, do whatever you want.


Note: Sorry, I did not see that this was mentioned above.
 


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Intuit

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#20
I would encourage people not to try this, you can do damage to the car by letting the gas level get down close to empty. You can suck in sediment and other crap from the bottom of the gas tank, and you also risk overheating the fuel pump if it's not covered with gas.
Speaking of which, anyone replace their fuel filter yet?
Wonder where and how many for this one.
In my previous vehicle it was attached to the firewall, post fuel pump.
That vehicle had a vacuum regulated, relay switched, electric tank mounted fuel pump outputting 38 PSI.
I remember thinking, the aftermarket fuel filters for that car weren't exactly confidence inspiring.


.
 


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