azzaboynt

I've just hit 1500km on the odo (I admit i'm not driving around much, damn work) I've noticed my warning light comes on when the needle is just under the 1/4 mark.

This usually translates to what I think is approx 10 litres of fuel in the tank. Is this right? I think it's a bit early for the light to come on?

Seems silly I guess but my last car (1994 Astina SP) the warning light used to come on when the needle was almost on the empty mark, meaning "buddy, get yourself to the petrol station now or else i'm gonna refuse to move" or at around 3 litres.

So, is this normal? or have all "Modern" cars (ie. less than 4 years old) got an overzealous fuel warning light system?

Cheers,
Azza

Revolver

Azza

Haven't noticed a similar problem with mine. I've run my tank quite low at times (well below 1/4 full) and haven't experienced a warning light yet.

mikeyr

Nope mine goes well down, I've only seen the light once.

Sigma

For what it's worth, my Mazda3 will go 67 highway miles after the light comes on. Yes, unfortuantely, I know exactly how far it will go (long, embarrassing story). And my Mazda6 I once took 69 miles after the light came in and was only able to stick 16 gallons in it (18 gallon tank) -- so I could have technically gone well over 100 miles after the light came on.

I don't own an RX-8 yet to tell you, but I am one of those that runs their tank to the light every time and usually add 10-25 miles, so I will be able to in the future.

But, while both the 6 and 3 give early warnings, neither come on anywhere near the 1/4 line. Both go off at almost exactly 1/8.

sco

Would be interesting to know how many litres you filled the tank with when you get the light (and compare that to the published capacity). My light comes on at about an 1/8th of a tank (according to the gauge) and it's when there is about 10L left.

There could be a calibration problem with your fuel level sensor causing the fuel light to come on prematurely.

timbo

My light comes on at about the same point, and I have run 80 (highway) Ks thereafter -- but was getting very nervous! I filled 57L at the next fill.

kiwimeat

Generally about 10l's left in the tank when the warning light comes on for me. At this point the needle is about 1/8 to go.

After ignoring it yesterday I "had" to fill up today (114.4/l!). Came to 50.47litres.

I'm more bothered by the completely indecisive fuel indicator needle that actually rises and falls (often by a bar or more at a time).

A digital fuel readout would be good but I guess then they would have no reason not to provide a proper trip computer in and that would be plain depressing - imagine watching the km's left in tank value.

azzaboynt

last 3 fills when the light came on, i put in between 55-57L in the tank.

It does seem weird eh? I'll take a pic and send it to the service dept the next time it comes on.

sco

Hmm.. a digital readout would be worse than what you're getting with the gauge . We can get the raw fuel level reading in scanalyser which we convert to a percentage (basically we get an 8 bit value which we multiple by 1/255%/bit. It varies wildly as fuel moves around in the tank. There is some calibration involved too... For me, when the car is full I get 89% or so back as a raw reading. I haven't run mine 'til empty but Hymee and Wildcard have and empty returns a raw reading of around 5%.

Wildcard

Yeh, that sucked. Conking out with 5% supposedly remaining. I had gone about 60km on the light before that though.

Is your light staying on just below 1/4 remaining, or is that just when you get the first signs of the light? Mine comes on early if I am going up (or is it down?) a hill. On the flat though it's not on constantly until 1/8 to go.

EZZY

it happened to me once only.... and was like wtf?!?
sometime after a long drive, and turn the car off, when i came back and switch the car on, the needle goes about 1 bar lower... does that happen to anyone? dont usually pay attention to the needle, but that was on odd occations

azzaboynt

wildcard, i thought the steepness of the hill going up or down had something to do with it, however cruising on level roads it's the same.

I'll drive it some more and take a pic :D Heh heh heh any excuse to drive the 8 around and around and around!

RXP33D

my light comes on with 15 litres to the tank left...Im pretty sure
And thats just under the 3/4 mark.

But then, I might need to get my eyes checked.

Gomez

I've done 90 odd km's with the fuel light on. The tank took 59 litres when I filled up, so I could've gone another 20km's easy.

timbo

...maybe! Given my experience at track days, I would be wary of the fuel pump picking up the last few litres....and would you want it to, given the crap that might be in the tank??!!

Gomez

Yeah, fair call.....