Does "E" really mean empty?

[Sidestreet]

1993 SHO, drivetrain and instruments running normally (or at least well enough...), low fuel light comes on at 1/8 tank mark, needle currently resting on E, in the red zone.

Just out of curiosity, are there any "reserve" gallons left? 1 or 2?
Is the true empty point below the "E", perhaps?

Thought I'd ask first before seeing for myself... doing a lot of "running on empty" these days... $$$!!!

 

[F-22 Raptor SHO]

The fuel light comes on so early because the electric pump relies on the gas to keep it cool. If you always drive it to E, you will shorten the life of your fuel pump. I have run my car till the lowest part of the red before, then put 17.3 gallons in. When you go around the corner and the car starts to sputter, then you are in dire need of fuel. There is alot of fuel in there, but I wouldnt do that again.

 

[hawkeye18]

In most cases (every car is different), the gas light means you have ~5 gallons left. I wanted to see how far I could get on a tank of gas from pittsburgh to Norfolk, and I made it as far as the Yorktown weapons station before my car died at 426 miles. I literally coasted into the gas station cos the engine was dead. I had always thought I had the 16 gallon tank cos I could never put more than 14-15.5 gallons in, no matter how far I drained it down (well below E). Well, that night I put 18.4 gallons in, and the fuel needle was nearly a quarter inch below the red zone.

Ford fuel gauges were never known to be real accurate-like.

FWIW, I tried it again just for ***** 'n giggles the next time I made the trip, and I coasted into the same damn gas station at 426 miles. Does this say more about the car or my driving style? lol the same guy from before was on shift that night, he remembered me and said, "Didn't you coast in here the last time you came here?"

OBTW, the fuel pump died 2 months after that. Coincidence? i think not...

I don't ever let it get to where I have to put more than 14 gallons in. Half because I can't stomach the fuel bill! Gah!

 

[yamahaSHO]

The fuel light comes on so early because the electric pump relies on the gas to keep it cool. If you always drive it to E, you will shorten the life of your fuel pump. I have run my car till the lowest part of the red before, then put 17.3 gallons in. When you go around the corner and the car starts to sputter, then you are in dire need of fuel. There is alot of fuel in there, but I wouldnt do that again.

As long as it is pumping gas, it should stay cool.

 

[93rev2sev]

Modern Fords are designed to trip the light when there is 50 miles left at the current average fuel economy.

 

[LJRuddy]

My GT will die instantly without warning when it runs out of gas and it ****** me off... Every other car would still run just enough to go another ~mile or so (or a handful of stoplights) before it would **** itself.

My car has ran out of gas with a needle's width above the red. There were other times where my needle was a good 2 needle widths below the red and it still ran fine for a few miles...

 

[baySHO_510]

Well, that night I put 18.4 gallons in... OBTW, the fuel pump died 2 months after that. Coincidence? i think not...

The most I have ever been able to pump was 17.xx, and I was so paranoid about clogging up my fuel pump. In my first SHO many years ago I ran out of gas 2 or 3 times... shortly after my fuel pump died too.

 

[TYSHO]

I have a 92 with guages and when it hits the red, it goes dead...sometimes before it even gets to the red, too.

My 89 with stock gauges can dip below the red and then some, I never ran out of gas in that car.

 

[SASHO91]

and I was so paranoid about clogging up my fuel pump. .

So... you were paranoid about clogging your fuel pump up...... with fuel.......



riiiiggghhhttt.....

 

[LJRuddy]

So... you were paranoid about clogging your fuel pump up...... with fuel.......



riiiiggghhhttt.....

Some say that running your fuel tank very low/empty will cause the small amounts of sediment that sits at the bottom of the tank to get pulled into the supply line and clogging things up. Whether this is true or not, i do knot know. However, i believe this is what Baysho was speaking of.

 

[SASHO91]

The way he stated, it sounds as if he was concerned about the filling of the tank with 17.4 gallons and it clogging his fuel pump...

As far as sediments collecting at the tank.. I have seen 10yr old tanks that are clean, and I have seen sediment in a 2yr old tank. It is true, but, it depends on alot of things.

 

[yamahaSHO]

Some say that running your fuel tank very low/empty will cause the small amounts of sediment that sits at the bottom of the tank to get pulled into the supply line and clogging things up. Whether this is true or not, i do knot know. However, i believe this is what Baysho was speaking of.

I've heard that too, however, if it's setting at the bottom, it can always be sucked up. There is a "sock" on the pump to collect that type of stuff, as well as a fuel filter.

 

[naval-avi8or]

As long as it is pumping gas, it should stay cool.

Incorrect, the more fuel you have to circulate and exhange the heat the cooler the pump will operate. That's why early indications of a failing pump exhibits failure when running below 1/4-1/3 of a tank and higher ambiant tempatures.

I chased this issue for years but only had problems during long drives, heat of the day during the summer (above 90 deg), when trying to streatch my tank for milage. Since I only did this once/twice a year I could never figure it out because by the time I could get it looked at the problem could not be duplicated. Day to day driving would never allow the pump to fail. Give the pump a few min to an hour and it would fire up like nothing was wrong. I was just lucky enough once that it happened at the off ramp to a FORD dealership and they gladly replaced the failing pump.

 

[yamahaSHO]

Sounds like you just had a failing pump that acted up under these conditions. The fuel is constantly being heated up from the hot engine bay around the fuel rails. It also has some cool down time on the way back to the tank.

The pump is literally cooled as it pumps gas through the unit.

 

[NoSHOAllGo]

Speaking of the fuel light. I noticed my gas gauge needle moves to half a tank, back down to an 1/8 of a tank, then back to the actual gas meter. Basically moves uncontrollably up and down.

 

[naval-avi8or]

Sounds like you just had a failing pump that acted up under these conditions. The fuel is constantly being heated up from the hot engine bay around the fuel rails. It also has some cool down time on the way back to the tank.

The pump is literally cooled as it pumps gas through the unit.

Yes mine was failing like I stated. The more fuel in the tank is directly related to the operating temp of the pump. Next time you need something to do see how long it takes to boil a quart of water vice 5 gal of water with the same size heat source (**** just note the difference to raise the temp 5 deg) and I think you will have a better understanding of thermal dynamics.

 

[yamahaSHO]

Yeah, I completely understand that more fluid takes longer to heat, however, the gas shouldn't be so hot that it's killing a good pump.

 

[F-22 Raptor SHO]

As long as it is pumping gas, it should stay cool.

then why put it in the tank?

 

[AREA 91]

The fuel pump is cooled by being submreged in gas, not the gas flowing through it.

 

[yamahaSHO]

Let's test that theory... Submerge it in fuel, however, run a hose off the end so that it is not allowed to suck up anything but air. I think yo know where I'm going with this.

Being submersed in cool lequid will help keep it cool, however, not pumping fuel through it will destroy a fuel pump faster than running air through it while submersed in cold fuel.

then why put it in the tank?

It is less likely to start a fire.