Fuel warning light

[DavidL]

I happened to run my car quite empty yesterday but the light did not come on.
Now I don't know how empty but the needle was on the bottom line.
Obviously the light may not be working so I checked with just the ignition on so all the warning lights lit. Now the oil pressure and voltmeter red sections at the bottom did light but the fuel (bottom) and temp (top) did not.
Is this correct can anyone tell me or am I missing 2 warning lights?
The gauges themselves work fine (I think!)

 

[Diver944]

No there isn't a bulb check for the high temp and low fuel bulbs [&:]

The low fuel light on both my cars only comes on when the needle starts to come out the bottom of the red zone on the fuel gauge. At that point there are around 8 litres left, I have done about 30 miles with the light on before []

The only way you will really know is by carrying a spare can and just keep on driving until it comes on (or doesn't)

 

[Riverside]

ORIGINAL: Diver944

No there isn't a bulb check for the high temp and low fuel bulbs [&:]

The low fuel light on both my cars only comes on when the needle starts to come out the bottom of the red zone on the fuel gauge. At that point there are around 8 litres left, I have done about 30 miles with the light on before []

The only way you will really know is by carrying a spare can and just keep on driving until it comes on (or doesn't)

Nothing to add except to say mine's the same, the fuel light comes on once the needle's gone all the way to the bottom of the gauge. My old 944 did too.

 

[TheFiend]

ORIGINAL: Diver944
The low fuel light on both my cars only comes on when the needle starts to come out the bottom of the red zone on the fuel gauge. At that point there are around 8 litres left, I have done about 30 miles with the light on before []

I usually do about 60 miles with the low fuel warning light on before chickening out.

 

[DavidL]

If you take out the boot carpet and prise out the big plastic plug over the fuel tank sender, you can disconnect the grey/white wire from the sender. Earthing this wire should light the bulb in the gauge if it's working. If that works, and you're still worried about it not coming on, proceed as peviously suggested with a spare can of fuel and keep driving. You COULD pull the sender unit from the tank and test it on the bench, but you might want a new gasket for refitting, and I'd never recommend opening the fuel tank unless you're really confident, or fireproof. []

HTH

 

[944 man]

Its under the rear load deck carpet. Theres a woven glassfibre pad over the plug though, so youll have to 'spoil' the car in order to find it. If your car were my car then Id run the tank down with a gallon in a spare (doesnt everyone carry a 5 litre can full anyway?).

 

[zcacogp]

Ummm, I'm not sure if it is true or not, but I have heard stories about cars which are run to 'dry' having problems re-starting as any grot in the tank is sucked up and pushed through the fuel system. It will be caught by the fuel filter (as long as there is one fitted, which there should be), but can cause problems with blocking it up.

If this is true (and I can't vouch for or against it), running to dry just to check the light is perhaps something to be avoided.

(For reference, the light on mine works fine but does come on right at the very bottom of the 'empty' line. I've never had the gumption to do more than about 30 miles with the light lit, particularly after having heard stories like the ones I just mentioned.)


Oli.

ETA: Here's another way of looking at it. I believe my car has an 80-litre fuel tank. When it is empty to the point that I normally fill it, I generally get around 62-65 litres in it. This suggests that there is at least 15 litres left below the point where I think "she needs more juice". I rarely get as far as lighting up the 'low feel 'light, which suggests that this light comes on when there is less than 15 litres left.

 

[944Turbo]

Ref Oli's first point the fuel take out is at the bottom of the tank, i.e. no matter how much fuel is in there the fuel comes from the bottom, so it is unlikely that when the tank is empty you risk getting more crud into the filters - unless the crud is floating, in which case I would imagine you could see traces of it when brimming the tank.
Tony

 

[DavidL]

ORIGINAL: 944 man

Its under the rear load deck carpet. Theres a woven glassfibre pad over the plug though, so youll have to 'spoil' the car in order to find it. If your car were my car then Id run the tank down with a gallon in a spare (doesnt everyone carry a 5 litre can full anyway?).

Fair point, O namesake... I must admit when I last pulled the sender it was on my old 924, while removing the tank for repair, so no option there. The S2 remains "unspoiled" [].

Also, Scotty, I think it applies to all variants, there should be 3 wires, one for the variable resistance "signal" for the gauge, one on/off for the light, and a ground, IIRC.

 

[Diver944]

ORIGINAL: 944Turbo

Ref Oli's first point the fuel take out is at the bottom of the tank, i.e. no matter how much fuel is in there the fuel comes from the bottom,

I've never run out in the 944 but I have in a couple of other cars over the years whilst checking how accurate the gauge is. Simply filled it up from the spare can and afer a couple of turnovers to pump fuel up the lines to the cylinders they both started up fine.

As Tony said, the fuel already exits out the bottom of the tank so running it dry 'should' pose no extra risk to crud pickup