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-   -   At what point does the 'low fuel indicator' come on? (https://www.team-bhp.com/forum/technical-stuff/167461-what-point-does-low-fuel-indicator-come-3.html)

When we fill at a pump, we usually overfill, till the brim of the fuel filler. The space between the filler and the actual tank can accommodate some fuel, maybe 1-2 litres, thus letting us fill more fuel than the actual fuel tank capacity.

For Safari Dicor which has a fuel tank of 65 liter capacity, the low fuel light (Amber) comes up when it has about 5- 8 liters left in the tank. Oddly I noticed that some times when you drive under the low fuel level, the engine cuts off until you shut off the AC. Once you turn off the AC, the engine runs as if nothing happened.

I noticed this on many occasions. Once I reached the border of Goa in the night after a long drive from Madras and I had to cut off the AC till I found a fuel station some 60 km away from where the low fuel warning light came on.

The Vento's MID automatically changes to the DTE display the moment fuel runs low. Meaning say you had it set to current trip time or average FE (my usual defaults) the moment DTE dips to 50 it automatically changes to the DTE display. And then the number keeps going down from 50 in multiples of 5 to 0. This is useful because it is typically at DTE=0 that the reserve (approx 5litres) kicks in. So effectively VW is warning you from the time you have about 10 litres left (approx 20% tank capacity).

This is important because it allows you to plan to refuel before panic stations ensue! I am really shocked that the 17L Creta lacks the DTE feature so that this kind of logic can be built in.

That reminds me of an old warning while learning to drive diesel cars... Never drive a diesel car on emergency/reserve because the engine TAKES IN air ("sucks in air") .... Causing an air lock or something to that effect... I had one such incidence in my old Indica.. The engine shuddered and kind of hiccuped.. I got scared and shut it off and asked an elder and he asked me ..are u driving in reserve and I said yes. He reprimanded me and got me to fill it up immediately . But then I restarted the cars smoothly and drove to the very near petrol pump and got it topped. Never to repeat this thing ?
So how correct is this warning ?

Interesting thread. My Fluidic Verna petrol has a capacity of 43 litres. I have noticed multiple times that after the low fuel lamp comes up, and I spend say an additional litre before tanking up, it always accomodates only 33.xx litres before first auto cut off.

That leaves about 11 litres and for practical purpose may be 6-7 litres for consumption after lamp. So, may be there is 60-70 kms range available. I have gone upto 35 kms approx but not beyond.

Also, noticed that DTE at the glow of lamp is about 65 kms and after a certain kilometres it just vanishes and shows --:--. And I can tell you that's a scary feeling.

As a best practice its good to tank up at half tank mark to minimize vopriazation, liquid sloshing in tank and the psychological heartburn when you pay for tankful stupid:

Another tip for efficient and actual fuel going inside is by keeping the nozzle latch at the first position on the fuel filler.

Any pump attendant will put the latch at 2nd or 3rd so that he can fill the car quickly and actually fill less due to vaporization happening due to fuel gushing-in.

So if the latch is kept at 1st position(The slowest speed), fuel fills at a steady rate and you do get more.

Mine is Palio Sport nv - 2004 model.

I remember the manual stating that 'low fuel indicator on' indicates a fuel level of ~ 7 litres.

During one top up, without the fuel indicator on, I have filled nearly 42 litres (by rocking the car, could fill nearly 2 litres). It means the tank capacity of Palio is more than 45 litres (as stated in the manual). Read somewhere that the amount of fuel in the pump and fuel lines will also add up...

BTW, I have driven 48 kms once with the indicator on. That could probably be the only time when I used the lightest touch - thankfully, there were no issues.

OT - One of my habits - when I fill in the normal course, I add System G. When the tank is close to empty, I tank up with Speed / Power / Shell Super - it really makes a difference.

The Fluidic Verna CRDi shows the low fuel indication when the DTE is 70 - 75 KM. However, how much more it can go is dependent on the average fuel efficiency calculated at that time, which varies in city and highway. After the light shows up, the DTE do not always go down in proportion to the KMs I drive. If I am on a highway, the DTE go down a KM for every 2 or 3 KM I drive and on city, it go down about 2 KMs for every KM I drive.

I had an experience where I was forced to drive for 70 KM after the low fuel warning lamp showed up. The DTE was 70 KM when the warning showed up and it went blank when it was 40 KM, I had to drive another 30 KMs with a blank DTE before I could refuel. That was a tough choice and I never let it run for more than 10 KMs with the warning lamp on, ever since.

The indicator lights up somewhere near 6 L of fuel or close if I remember correctly.

So taking the current average it's giving in City area which is 16 it can do at least 90-100 kms more when the light comes up. Not bad.

Does that mean, most of us are being ripped off, we are paying more for less fuel. Or is it that even when the latch is at 2nd or 3rd level the quantity of the fuel remains the same, no matter the filling speed.

Depends on the car. My Civic comes on with about 10 litres left, while the Brio with about 7-8. In my older Santro it was about 6 litres.

Sorry to quote myself - but just an update....

Dug out the manual after posting. The manual clearly states the following -

a. Fuel tank capacity is 47 litres.

b. When the low fuel indicator comes on, it means there is reserve fuel of ~ 5.5 to 7 litres left in the tank.

My palio runs hardly 30kms after the light glows. I've found this out, Painstakingly. The Manza, I've run ~40kms, IIRC, the Ikon doesnt have one, the Jeep :D:D, and the Fiesta I've never tried it at these levels.

Its far too expensive to change the fuel pump, than running at low fuel. I try as much as possible to avoid seeing the light. Nowdays, with so many pumps, its pretty easy.

Can you please elaborate? How does faster flow rate mean more reading in meter?

As per my understanding, when the fuel tank is near empty and when the nozzle latch is kept at 2 or 3 position, fuel flow is faster hence creating more vapors inside the tank and the fuel filter understanding it to reach the auto cut off point before the fuel actually being filled.

Hence keeping it at higher latch position means lesser quantity filled in. Am I thinking wrong?