Mazda Mazda 6 (2002 - 2007) - 2.0 diesel -fuel warning light and remaining miles

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Mon 10 Dec 2007 17:49
2.0 diesel -fuel warning light and remaining miles - rtj70
I have had my Mazda6 2.0 diesel since late October. This week I let the fuel run lower than usual before re-filling (waiting for my fuel card but that's another story)...

... so it had got down to below a quarter of a tank with the "miles remaining" readout heading to single digits. All fine but the fuel warning light had not come on. Decided to see how low it really got and fitted almost 54 litres in. The tank is meant to be 64 litres so I had just over 10 litres left...

Does this sound right? Miles remaining basically saying the car was very nearly empty but the fuel warning light had not come on. And if I had 10 litres left I could have gone a lot further... like maybe 100 miles! Which would have meant well over 500 miles from a tankful with a fair bit of round time driving too...

I'm wondering what the "miles remaining" reading would have done now when it reached zero. At least I know the fuel gauge is more accurate than the pessimistic digital readout. Didn't want to risk it this time first time not knowing which was lying.

Anyone else seen Mazda's fuel gauges and estimated miles remaining behave like this?

Cheers

Rob

Edited by Dynamic Dave on 10/12/2007 at 18:49

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Mon 10 Dec 2007 18:41
Fuel warning light and remaining miles - Ruperts Trooper
It's inaccurate to calculate fuel left as " tank capacity less amount put in" - because of air gaps and variations in fuel pump cut-off - you could be several litres away from "full".

Back in the '80s and early '90s, one of my first jobs with each new car was to note how many miles could be travelled, at motorway speeds, with the warning ligh on until running out of fuel - I did always carry 5 litres in a can - this gave me a good guide as to the fuel gauge reading at low fuel levels.

Since the installation of catalytic converters it's not recommended to allow the car to run out of fuel so I've discontinued that practice.
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Mon 10 Dec 2007 18:45
Fuel warning light and remaining miles - grahamw
I had a Mazda6 2.0 diesel that ran out of fuel.
The computer indicated that it had enough fuel to travel another 46 miles, from memory the warning light was on.
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Mon 10 Dec 2007 21:17
Fuel warning light and remaining miles - rtj70
"computer indicated that it had enough fuel to travel another 46 miles"

Interesting. Mine said remaining miles was only 6 when I refilled but I got just under 54 litres in including the second click of the pump. The tank is 64 litres so there mus t have been a fair bit still in even if not a full 10 litres.

And the low fuel light was not on and the needle only part way below the quarter mark.
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Mon 10 Dec 2007 22:51
Fuel warning light and remaining miles - kingslea
If we talk fuel consumption in the pub (sad), people quote the fuel computer figures and actually believe in them. One guy has a BMW 325, his computer gives over 40mpg. My Mazda 6 diesel says 50 mpg, they are both at least 10% optimistic. The only way is to brim the tank, mine then gives me a realistic 44mpg.
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Mon 10 Dec 2007 22:57
Fuel warning light and remaining miles - rtj70
I only work out mpg by brimming the tank - the readouts are nowhere near accurate. They usually are optimistic. But today the miles remaining was saying 6 with 10 litres left... I would not trust this for sure and with this being a new car I did take it's word in case the fuel gauge and missing warning light were the problem.
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