Low fuel warning light Astra - oldpostie
I tried to find out just how much petrol is left in the tank when the warning light first comes on, but the book just calls it the reserve area.
Strangely enough, when I came home today my usual garage was coned off after a spill, so I had to go to a more expensive one. When I got there, the orange light was on constant, but after putting in just £5, the light started flashing. It hadn't been flashing before. There is a red warning when you are much lower, but the orange comes on soon after the needle enters the last section, just under 1/8 full, according to the gauge.
Wondered if any more information was available. Any ideas ?
The car is a 2005 Astra 1.6
Low fuel warning light Astra - Falkirk Bairn
When the light comes on FILL THE TANK. until it is brimming.

Subtract that from the tank capacity (in your handbook)

Bingo - you have the reserve capacity in litres
Low fuel warning light Astra - oldpostie
Thanks for that. I've just filled it, rather than try to do that at 4 a.m. tomorrow !

There was about 7 litres left when the orange light started to flash. I don't think I'll rely on it though.
Low fuel warning light Astra - Dynamic Dave
I can't be exact, but it's something like 2 gallons left when the light first comes on. When the light then starts flashing it's telling you to hurry up and refuel ( a sort of final reminder to hopefully catch your eye, because a flashing light might be more noticable than a static one)

I realise you said the light started flashing after putting in a fiver, but I imagine your ignition would have been off whilst putting that fiver in and would have given the float in the tank time to settle down after being sloshed around whilst you were still driving.
Low fuel warning light Astra - Armitage Shanks {p}
When the fuel gets low in my 307 the light comes on steady, with an audible click from some relay. The book says that one then has 30 miles (approx) and adds that a flashing low fuel light means a faulty fuel gauge. In my car 30 miles equates to about 3 litres remaining.
Low fuel warning light Astra - Ruperts Trooper
Mk4 Astra '98-'04 - the low fuel light comes on at 5 litres remaining and starts to flash at 3. Tank full capacity is reached when 2 litres have been added after first pump "shutoff".
Low fuel warning light Astra - Victorbox
I normally fill my Zafira when the warning light goes orange but recently let the warning light flash for half a day because the petrol in Bristol is several pence per litre cheaper than out in the sticks. This meant the gauge was not moving off the bottom for about 15 to 20 miles. I managed to get 58 litres into the tank to brim it thinking the tank was 60 litres only to find the handbook says capaciity is 56 litres! So it must have been pretty near empty.
Low fuel warning light Astra - piston power
i wouldn't wait till the light comes on i fill up at a 1/4 so as not to pick up any crap that maybe in the tank!!!
Low fuel warning light Astra - oldpostie
I try to do this, it's just that my usual place had coned off the pump area, so I had to keep going.
It reminded me of what my great-uncle told me. He had the garage in Blakesley, Northants, for years, and during the war most cars were laid up. The village doctor was allowed petrol, though not as much as he would have liked I suppose. He was frequently bringing his car in, or at least, needing fixing, because the lack of petrol, and low level, caused the carb to get blocked. Uncle's regular job was cleaning the jets.
Low fuel warning light Astra - Hamsafar
I find that you have about 2 gallons when you don't really need it, and 1 gallon when you're on an unfamiliar motorway at night with no services, and you're slowing down and wondering whether to come off or press on.
Low fuel warning light Astra - blue_haddock
I can get 47 litres in my 106.

The fuel tank only holds 45.
Low fuel warning light Astra - David Horn
What possible cack can you get at the bottom of a modern plastic tank?
Low fuel warning light Astra - Dynamic Dave
cack from the filling stations fuel tanks - which are still steel.
 

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