Low Fuel warnings

[mpaton]

I thought I had understood the manual about the meanings of the 2 low fuel warnings,

The last bar flashing
and
all bars gone and fuel pump and X scale of gauge flashing.

However, I have a third warning which seems to coome in between those 2 as the tank goaes down.

It has the last bar and the pump and the X scale all flashing. I think this is what happens when you first turn the ignition to ON, and it persists for a few miles until it is replaced by one of the other 2 warnings.

Of course my sample size is a whole 2 tank fills so far, so I may be confused :-)

I'm trying to evaluatehow far I can really go once the tank gets low, and before the shrill anxiety levels from the other seat get too high. :-)
The larger of my 2 fills was 8.099 US gal.

I was perfectly satisfied with my fuel usage, but I'm obviously not in the same league as some of the people here!

On a more technical note, does anyone know the RPM at which DFSO is disabled as engine speed in gear drops?
(DFSO is Deceleration Fuel Shut Off).

It would be higher for the automatic than the manual (assumping the torque converter unlocks at closed throttle)
Assuming one can use a little extra engine braking, it should use less fuel to come to a stop in gear until DFSO disables, than it would to coast with the engine idling.

[ThunderG]

The lowest I've driven on fuel is 30 miles after the last bar went off and the whole fuel display started flashing. It took 8.5 gal to fill at this point. It looks like I should be able to drive around 60 miles after it shows empty if the tank really holds 9.2 useable US gallons. I would like to hear if anyone has run out of gas and how much did it really take to fill.

[alex16]

Most I've done is about 7.9 gallons us, my entire gauge was flashing for about 15 miles. It's good to keep about a gallon left in the tank to keep the fuel pump "lubricated" and cool, fuel pumps don't like to be ran dry and at about 1/2 a gallon your fuel can easily slosh in the tank giving short periods of dry conditions.

[25Plus]

When I got my Space Star from the car dealer, 7.8 gallons (29.7 liters) could be refuelled up to the filling hole. My next two fills showed about 7.6 gallons (28.9 liters) when driving about 20 kilometers after the first warning. The manual says, that 6 liters should be remaining in the tank with the first and 3 liters with the second warning, but I don´t know how long I can drive then without running out of fuel.

My Daihatsu has a 36 liter Tank with about 8 liters reserve, therefore I drive about 100-140 kilometers after the reserve warning flashes and filling up about 9 gallons (34 liters).

Your first post leads me to hope, that I can use about 8.5 gallons (32 liters) with the Space Star, too. That means driving about 75 km more with a filling.

[JimInMichigan]

The fuel tank ( and related component's ):


Looking at the above image, I think it is a mistake to allow your fuel get below 7-8 gals. As mentioned above, the fuel pump relies on fuel to keep it cool. It's fun to see how far you can push the envelope, but doing so frequently could end up costing you a big repair bill later ( $600 just for the fuel pump assembly ).

[alex16]

This is true when running the fuel pump "dry". when the fuel is not surrounding the pump completely it does not really hurt it, the diagram looks like the fuel pump is at the very bottom where it is on every car I've ever worked on with efi (except some that have a secondary fuel pump on the frame). I ran my 1999 civic below a gallon every tank for years, 230k miles no issues, had chevrolet's 12 years old with less than 100k with fuel pump failures that were never ran below 1/4 (fleet vehicles topped off regularly). Quality of the pump and design play a big factor, running low won't hurt them other wise they would note it in the owners manual, when my entire gauge flashes I get fuel, normally 7 to 7.5 gallons. If the fuel pump does fail I am sure there will be plenty of wrecked Mirages out there to find a replacement by then, and its easy to change under the back seat

[25Plus]

My Daihatsu has the first fuel filter and the first fuel pump since 265000 km (everytime emptying the fuel tank to one gallon), therefore I don´t think there will be problems with my Space Star at all. But we will see .

[JimInMichigan]

Quality of the pump and design play a big factor, running low won't hurt them other wise they would note it in the owners manual,

Just like they warn you that you should avoid pot holes because the rear alignment is not adjustable? Oh wait, they don't mention that.

when my entire gauge flashes I get fuel, normally 7 to 7.5 gallons. If the fuel pump does fail I am sure there will be plenty of wrecked Mirages out there to find a replacement by then, and its easy to change under the back seat

So you have 1.7 - 2.2 gals left. Seems adequate to me.

Here are a few quotes with links:
http://www.consumerreports.org/cro/n...stly/index.htm

The gasoline acts like a coolant for the electric fuel-pump motor, so when you run very low, this allows the pump to suck in air, which creates heat and can cause the fuel pump to wear prematurely and potentially fail.

http://www.bankrate.com/finance/auto...r-myths-1.aspx

Where your dad may have been right is that you should always try to never run out of gas. That fuel pump inside the gas tank relies of the gasoline to keep it lubricated and cool, and if you frequently run out of gas you could cause the pump to fail.

The good news is that the "low fuel" light comes on when there's anywhere from 1 to 2 gallons left, which is plenty to keep the pump safe.

So it's OK to run the tank down to where the warning light comes on, but you should then get gas as soon as possible.

http://www.boston.com/yourtown/somer...ng_out_of_gas/

For the lowdown on running empty, I turned to some trustworthy sources: John Paul, American Automobile Association of Southern New England’s “Car Doctor,’’ and Butch Ferraro and Tony Izzicupo, owners of Salem Street Auto Clinic in Saugus, who have been fixing my family’s cars since I was a kid.


Fuel pumps in modern cars, the mechanics explained, sit in the middle of the gas tank, surrounded by cool gasoline.


When your tank’s empty, the fuel pump burns hotter, inviting wear and tear, and if you consistently drive around with your gas gauge near empty, you run the risk of burning out the pump.

You guys can do what ever you want, I am just trying to help. Mitsu's warranty coverage of 5/60000 will cover you until then. But if you plan on keeping your little car for a longer period, keep this info in mind.

[JimInMichigan]

I just looked, the 10/100000 power train coverage includes the fuel pump. So this isn't an issue for those keeping their car in that mileage period ( as long as your the original owner ). Again, just trying to help.

ENGINE:
• Balancer Belt and Related Parts
• Balancer Shafts
• Cylinder Block and Internal Parts
• Cylinder Head Assemblies and Gaskets
• Engine Mounts
• Flywheel or Drive Plate (Including Ring Gear)
• Fuel Pump
• Intake Manifold
• Oil Pan and Oil Pump
• Timing Belt and Related Parts
• Valve Covers and Valve Cover Gaskets
• Water Pump

[cortisol]

I just looked, the 10/100000 power train coverage includes the fuel pump. So this isn't an issue for those keeping their car in that mileage period ( as long as your the original owner ). Again, just trying to help.

Very good info you posted on the topic