Running car on empty tank

Always run it till it's almost dry and fill it full. Can't stand people who make me queue at the petrol station and then only put in £10?? Filling up with a petrol is a pain.

My car has a 'reserve' though, still part of the same tank but the final gallon of fuel is not calculated on the fuel gauge or trip computer. Driving around with a range of 0 miles takes some nerve though! :)
 
I've yet to see my fuel light come not. Thats probably because I don't have one. I fill up when I start edging under 1/4 of a tank, I don't usually wait for it to go to low.
 
craig_kennedy83 said:
Im sure i did read/hear a while back that running on empty was bad as the flow of petrol can be interrupted, which would be bad!
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How does the ignition cut-off work? I suppose it doesn't just cut power to the fuel pump, otherwise there'd be a slight delay before turning off, but unfortunately I don't know enough about engines to work it out :/
 
just run the Fiesta ST on 0 for 20miles. Still had 2litres left in the tank when i filled it up so hmm i wonder how far i can really go.

But then i guess if i ragged it to the petrol station i would have runout half way there. (currently low on funds, so getting 38mpg with my current driving "style")


miniyazz said:
So - here's a few conflicting thoughts on whether or not driving with an almost empty tank is bad, and why. What do the rest of you think on the matter?
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as said in the other thread you quoted those other quotes from, most modern cars recirculate fuel from the tank, to the injector rail and back to the tank constantly to keep high pressure at all times. Obviously at max throttle very little will be returning, but at low throttle i should imagine 90% of the pumps volume heads straight back into the tank.


The only real reason for not running the tank dry is that its often hard to get the fuel running back through the lines, particularly on diesels.
 
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miniyazz said:
How does the ignition cut-off work? I suppose it doesn't just cut power to the fuel pump, otherwise there'd be a slight delay before turning off, but unfortunately I don't know enough about engines to work it out :/
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The injectors. Theres not a open hose on the engine from the fuel pump.
 
There are a couple of things here. Firstly I've taken a few tanks off cars and they have never had crap in them, except for one which sat empty with no cap on it for about 15 years. That's the only tank that's every given me problems. Second, the fuel pipe draws from the bottom of the tank. Third, banging over speedbumps, cornering, braking etc sloshes all the fuel around and would disturb any crud if it was sitting there. Finally, there's almost certainly a fuel filter on the car so any debris that might have found its way in will get stopped there.

miniyazz said:
Who else carries round a few litres of spare fuel, just in case?
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I do, but my fuel gauge isn't very accurate. I think it's why Ford referred to them as fuel indicators, not gauges :D
 
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First I see fuel indicator go into red, then below the redline, then the fuel light comes on on the dashboard, the trip computer says I can still go 80 kilometres and when that says 10 kilometres to go I fill up again, I have been doing this for years now without issue.
 
In a 320i in South Africa I had the empty light on a very long very baron road without a Garage in sight both on GPS and visibly.

I drove like an absolute SAINT and did ~90kilometers. I have no idea how much longer it would have gone :o
 
My F reg Polo was never the same once I ran it dry :( I cleaned the carb out and everything must have have had some crap lodged somewhere!
 
Interesting that despite there being little mechanical evidence to support it, there are people who have had problems after letting it run dry.

jegz said:
My F reg Polo was never the same once I ran it dry :( I cleaned the carb out and everything must have have had some crap lodged somewhere!
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Did you try changing the fuel pump? As that has been suggested as a potential problem, though I wouldn't have thought so on just one empty tank.
I wonder if carburettors react differently to injectors wrt not having enough fuel, did you ever try replacing that?
 
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