Does each bar stand for 1 gallon?

[swng]

Originally Posted by Driver:
"You should really never let you tank get below 1/4 (two bars) full. That keeps all the crap that gathers in the bottom of the tank from getting in the engine. I've done this with every car I've owned and the Yaris manual even suggests that you don't let it get lower than 1/4 full."

Agreed fully.
Apart from the technical reasons (I believe there can be many, including some that I don't even vaguely understand for sure) to leave the tank at least 1/4 full, from a practical point of view, it makes good sense to always have a car that can go one hundred kilometers plus (60+ miles) ready. One never knows when an emergency trip is needed when no time can be wasted in refilling or when there is actually no place/opportunity to refill.
From a fuel economy angle, more fuel left in the tank also means more waiting time for the gas price to drop from a temporary high. Don't ask me how to know when is a high price temporary though. It may just be subjective judgement or intuition
On the other hand, PetersRedYaris' method is good. If it can be modified to, say, refill once the third last bar disappears (that means two bars remaining), it is still a simple and useful method to help gain a fairly accurate impression on a car's fuel economy. May I invite you to post your various observations on fuel economy on the Fuel Economy Thread anytime?

[Typer73]

Originally Posted by Driver

You should really never let you tank get below 1/4 (two bars) full. That keeps all the crap that gathers in the bottom of the tank from getting in the engine. I've done this with every car I've owned and the Yaris manual even suggests that you don't let it get lower than 1/4 full.

Maybe I've been lucky? I also fill up when the bar flashes, because I always filled my previous car when the "red light" came on (both meaning about a gallon left). The previous car was a '92 olds cutlass, which now has 160,000 miles on it & is still going strong. If I can get away with it in an American car, I can sure hope to get away with it in a Toyota!

[Katana]

Originally Posted by Driver

You should really never let you tank get below 1/4 (two bars) full. That keeps all the crap that gathers in the bottom of the tank from getting in the engine. I've done this with every car I've owned and the Yaris manual even suggests that you don't let it get lower than 1/4 full.

Correct.

[keesue]

Does anyone know if there is an in-tank pump in the Yaris?

[eTiMaGo]

Originally Posted by keesue

Does anyone know if there is an in-tank pump in the Yaris?

Yup, there's a pump and a pretty complex system for collecting vapor and so on, so that it's a returnless fuel system.

[keesue]

Ah, thanks. Well, in that case, the reason Toyota says to fill up at two bars is because the fuel in the tank cools that pump. When it is allowed to run without being submerged, it gets hot. May not be an issue but its good to know why, eh?

[hystria]

Originally Posted by Driver

You should really never let you tank get below 1/4 (two bars) full. That keeps all the crap that gathers in the bottom of the tank from getting in the engine. I've done this with every car I've owned and the Yaris manual even suggests that you don't let it get lower than 1/4 full.

well, actually the fuel pump sucks always from the bottom of the tank. The pump is vertical and the suction is very close to the bottom of the tank and there is a filter bag to prevent sucking any dirt from there.

The real reason they suggest to keep a good fuel level is because it greatly helps to keep the fuel pump colder which prevents from premature wear, as the pump dissipates more easy the heat produced by the friction of the piston if immersed in a fluid. Apart this main reason, there is another one: the fuel tank is in metal. If the fuel level is low, humidity tends to appear on inside the tank. eventually, over the years leaking may develop by corrosion starting from inside. I've seen this on a 1990 civic, the tank was perforated and leaked although on the exterior there was no trace of rust (had anti-rust treatment).

[keesue]

Yep! Well said.