[robroys woman]

I’ve had an interesting problem crop up with my FR-S. It has a 13+ gallon tank and up until the 110,000 mile mark I was able to always get at least 75 miles past the “low gas light” coming on, and still only put 2.5 gallons at the most.

But with two consecutive tanks I ran out of gas at the 40 mile mark and was only able to put 11 gallons in. I now only trust it to 35 past the light coming on.

BTW, I have a 150 mile round trip commute. I fill up every two days.

[robroys woman]

2.5 = 12.5

[Blue Highway]

I have heard from people that it isn’t good to go “as low as you can go” towards an empty tank as it has a possibility of sucking in sediment or debris from the bottom of the fuel tank and introducing it in your fuel injectors which will cause them to clog. Not sure if there is truth to this but I try to refill my tank once it gets near 1/4 tank.

[Red Badger]

Change you spark plugs.
Don’t just clean and re-gap them.
Change your oil, filter and air filter.

Make sure your tires are properly inflated.

If it has a fuel filter in-line, change it too................

[1_Rain_Drop]

I was told to fill the gas tank with non ethanol fuel every once in a while to clear up the gunk in the bottom of the tank, or at least keep it at a minimal level.

[Yo-Yo]

Take it in to your Toyota dealer. I have no personal knowledge of the Scion FR-S, but a bit of googling turned up an known issue with them. It seems that the gas tank is really split into two subtanks with an interconnecting pipe.

It's possible that crud has partially blocked this pipe, so that you're no longer fully filling both tanks.

Here is a forum link explaining another guy's problem:

http://www.ft86club.com/forums/showthread.php?t=74249

And here is his hand-drawn schematic of the fuel tanks:

[moovova]

I had a Fiat once that the low-level red light stayed on so much...I finally burned it out.

[mazda77]

The injectors and the computer determine the amount of fuel dispensed at each tick of the pulse. As injectors are simply solenoids, the mechanical components and the passage orifices wear over time. As the pulse width may stay the same, if the injector orifice enlarges from erosive wear, the amount of fuel flow each pulse increases. Outside of changes in the feedback from the O2 sensor, the computer has no way of knowing how much fuel is dispensed per pulse.

I would suggest having a service done on the injectors and also replace the O2 sensor. To properly service and check the injectors, they must be pulled and tested externally.