[AP1]
I have noticed that it depends on the angle of the car. For instance I think in my car, when I am parked uphill, I lose a bar or two... when I am downhill for a while, I gain a bar.

I have seen the low fuel light come on anywhere between 1-3 bars. I think it's normal - I don't think it's a problem.
[/AP1]

 

when my light comes on i can only get about 10gal in the tank....which leads me to believe that there is a 3 gal reserve when the light comes on.

but i don't trust that damn guage...

ap2 btw

 

I had the same problem..it was a bad "send unit". Fixed under warranty Problem solved

 

Does anyone know for sure how much gas is left in the tank when the "low gas" light goes on?

I did an experiment once with a Toyota Corolla. I filled a gas can with fuel, put it in the trunk, and drove until the car ran out of fuel. By the time the light went on, there was still enough gas in the tank for 75 freeway miles. At Corolla's fuel efficiency that corresponds to approx. 2 gallons. Corolla has the same size tank (13.2 gal) as S2000. So, the space is distributed somewhat like this:
- 2 gallons of reserve
- 10.5 gallons of "measured" capacity
- 0.7 gallons of space near the top which is unused unless you "top up"

I wonder if it's the same on S2000.

 

One time, it took 30 minutes for my lights to reach FULL after filling up.

It moved up 1 bar every 5 minutes. After I filled up, I immediately went back to the gas station to fill up again, thinking that it didn't fill the first time...was so confusing to me.

Never happened again.

 

Currently, I own three Honda products. A 1998 ST1100 motorcycle, 2001 Odyssey minivan, and my 2004 S2000.


The low fuel light on the motorcycle will "start" to come on about the time the gas gauge reaches about a needles width off the empty line. The reason I emphasize "start to come on" is because it will fade on gently and then fade back off again. This is most noticable if I'm in hilly country. The light will fade on to full brightness going up hill and then fade back out until it's off going down the other side. Eventually it'll reach the point where it stays on full brightness all the time. If I pull in to a gas station about that point, I'll take right at 6 gallons even in a 7.4 gallon tank. The bike's been very consistent about that in the 45k miles I've put on it. I "like" the way it works!

The Odyssey and S2000 however, have never worked that cleanly. In both cars, when the light comes on, it comes on full and stays that way. If I go up a hill, or hit the brakes, or dodge a pot hole, whatever, that causes the fuel to slosh in just the right direction to make that light come on, it somes on and stays on. So, like you and probably everyone else, I've seen a pretty wide difference in how much fuel it takes to top off the tank when the low fuel light comes on. My Odyssey averages around 15 gallons in a 20 gallon tank but it's varied from 14.2 to 15.5 depending on the situation. My S2000 usually takes right at 11 gallons but I've filled up with anywhere between 10.5 and 11.3 gallons or so, again, depending on the situation.

Personally, I like the way the motorcycles works much better. It's been a lot more consistent overall.

FWIW!

Drive Safe,
Steve R.

 

Mine seems to be a bit off also, which baffles me. Aren't digital gauges supposed to be more accurate than analog?

 

^ apparently not.

Usually when the light comes uon, I squeeze in 10.4~10.6 gallons.

 

The read out on the dash may be digital but I'm pretty sure the signal coming from the sending unit in the gas tank is analog. Basically, all it is, is a rheostat with a float mounted to the arm.

"Very" basic technology, especially when compared to all the other computer controlled functions on the car.

Drive Safe,
Steve R.