"X miles before empty"

Don't keep pumping once the hose shuts off. You'll screw up your evap system and get an expensive check engine light.

 

my other car is an R56 mini cooper and HPFP failure is pretty common for the same reason. they recommend refueling once the first low fuel indicator goes on, usually around 65 miles to empty or 2+ gallons.

 

No need to panic at "0" miles remaining as long as there's gas stations in the general vicinity.

 

Yes, i know this, thus the 10 second burp and stop filling at pump shutoff... fuel will backflow into the evap canister and lines, and cause havoc with leak detection, and you have to replace the canister, and purge the lines from the fuel return/egr to the tank. also can cause issues with the purge valve..

 

Thanks for sharing!

 

as others have said, there is usually 2-3 gallons left in reserve once "gas empty please fill" illuminates. My previous 6 spd BMW M5 used to have a build in algorithm (based on gas consumption, not distance) to determine the exact miles left until empty: i.e., if you pushed in the clutch & coasted or were light on accelerator the "miles until empty" would lengthen & alternatively if you stomped on the gas the miles would dramatically decrease. Unfortunately our Taco's don't seem to be as "smart". Pushing on the clutch & coasting or stomping on gas does not appear to significantly change the "miles to empty"; it seems to be based on distance traveled alone.

 

It is actually fairly simple to calculate based off of the number of injectors, their capacity (rated in cc's) and counting the number of times they are fired times the pulse length is depending on AFR, and readings from the catalytic converters. using flow numbers (simple equation) you can be fairly accurate in fuel consumption, and compare against known fuel capacities, and levels. just have to remmeber that the bottomof the tank is curved.. so less fuel there than at the middle...

just have to have an accurate fuel level/meter or have the computer recognize a fuel fill up to "full" an aftermarket "long range tank", or secondary tank would screw this calculation up..

 

I've got An ultraguage in my truck. Once calibrated (more accurately than the dash guage which is almost always about a mile per gallon optimistic) the UG shows about 30 to 60 miles more to empty (calculated based on the size of the fuel tank I told it from the specifications in the owners manual), how much fuel it thinks I've burned (less than 3% error from pump) and how many miles traveled (less than 1% error from odometer)

Based on this I think the dash keeps a few gallons in reserve for its distance to empty calculation. The manual also says that it keeps about 3 gallons in reserve.

 

When you enter the tank in the UG how much did you put in? 21.1? Or by the amount of gas you actually put in from empty? I'm curious because I would like to calibrate my UG correctly to get an accurate reading of mpg as well as mileage.

 

I learned long ago, not to tempt running out, but if you are driving it you get a feel how far you can go. I've put a max of 19.5 in my 3rd gens. However in an unrelated incident my new bride 45 yrs ago asked me to fill her car with gas because it was low and she didn't like to use the pumps. I said sure I'll put gas in when I went to get diapers with her car. Made it 2 blocks. I have never let a car we own sit on E since. Being that guy walking with a gas can is embarrassing. Again that was with me not driving my truck pryer to that.

 

Who cares? Plan on filling up when you’re approaching 1/4 tank. Fuel pumps tend to live longer too when there’s enough fuel in the tank to cool them.

 

It's a suggestion more then anything. It's close but not remotely accurate.

 

maybe i'm missing something, but how could a section of the tank, in which the pump is submerged, be "unusable"? either the pump is sucking gas or it isn't.

 

This game has been played before. Unless someone has beaten me… I’m the highest ranked player of the game of chicken. Forgot what the number was, but consider that the “please refuel” warning starts at 2 gallons and the fuel is a coolant to the pump as well as minimizing debris on the intake filter. If you know your MPG, it’s easy to figure your remaining range… typically ~30 miles. Get gas when you can.

 

I’ve had my Tacoma 3 years now & have never had the low fuel light come on…I always fill up at 1/4 tank. The first & last time I ran outta gas was my first year driving (1982) & will never happen again.. learned my lesson..