How accurate is the fuel gauge warning light ?

Dogbreath

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Hi
Just curious as to how accurate the fuel warning light is compared to what miles are showing left on the readout.
My warning light came on today at Quarter tank, command was saying I had 40 mile left.... is this about right...? I never usually let it get that low as a rule..!
Cheers
Lee
 

fuzed

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Hi
Just curious as to how accurate the fuel warning light is compared to what miles are showing left on the readout.
My warning light came on today at Quarter tank, command was saying I had 40 mile left.... is this about right...? I never usually let it get that low as a rule..!
Cheers
Lee

Not sure, mine does the same, would also like to know! :)
 

AMGeed

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I wouldn't like to put it to the test to see how accurate it really is, but the mileage readout can be wildy inaccurate. Going up a hill the mileage can go down a few miles in a few hundred yards. Likewise, the fuel light can come on going up hill only to go out later on the flat or going downhill.
I'll always think about refuelling when the tank reaches around a quarter full.
 

SW18

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I'd been wondering about this: for me the light tends to come on when there's a bit less than 1/8 tank left, so I usually lose my nerve then and fill up. But I've never managed to get more than 71 litres in at that point, which means 9 litres to spare. That would easily be 50 motorway miles plus a couple of litres spare for 'fumes'. Still, I haven't fancied testing it out.
 

190

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My fuel light comes on at a pretty consistent gauge indication of 1/8th. Assuming the setting is slightly pessimistic i.e. there is a little more than 8 litres left then it seems accurate enough as it's supposed to be 8 litres left out of a 66 litre tank.

8 Litres will get me a minimum of 70 miles so it's hardly a worry. I haven't pushed my luck that far but I have done 50 miles with the fuel gauge not quite reading empty. On an old tech car I'd be tempted to experiment by deliberately running out with a 5 litre fuel can in the boot. Who knows what that would do to a modern car.
 
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The Quattroporte gave average economy in miles per gallon but the tank was in kilometres!

Plus once it got to 40km remaining the tank section would just go blank!
 

MancMike

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Very, I rarely put more than a tenner in and having had the car 3 years, I can tell how many miles I've got left by the the gauge by a fraction of a millimetre, I've never ran out.

It doesn't even run out when the gauge no longer lifts up off the stop.

It uses averaging algorithms to display an accurate reading in different driving styles, so if you're booting it for a bit, the needle can dip, pre-empting it continuing to be depleted at that rate. If you then suddenly drive like miss daisy, the needle can lift a bit again.
 
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Major774

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I always play the petrol game lol.

So far the max I have put in my car from almost empty is 77-78 litres up to the first click.
 

Mactech

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My experience is that most German cars are set up to display very 'safe' readings and I have a number of Mercs down to 'zero' miles remaining and never run out.
My biggest concern was when I set off to drive home from Magny Cours on a Sunday evening in an Audi A6 some years ago. They had just built the new road north to Paris, but had not yet opened any of the service areas:confused:
I got to 'zero' range, then drove another 53 miles before I finally found somewhere to refuel:eek:
I don't get too stressed about it anymore;)
 

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