Thousands of motorists a year are rescued by breakdown firms after running out of fuel. Is this a risk you run, asks Sue Hayward, who admits being too cheap to fill up the tank.
Do you fill up with fuel the minute you hit half a tank? Or do you trundle on until you're running on fumes and you risk coming to a spluttering halt?
A whopping 30 per cent of us wait for the warning light before taking a trip to the pumps according to Admiral Insurance.
And one in four admit to having run out of fuel, and not just once.
Stranded motorists account for nearly 50,000 of the AA and RAC's emergency callouts every year, which seems a huge number when it's something that could easily be avoided.
Running out of fuel
When it comes down to my car, its warning light regularly kicks in with 70 miles in the tank and I rarely fill up before it falls to 40 or 50.
Anything less and I admit I do get twitchy and fill up quick, unlike my husband who recently needed me to rescue him when he ran out of fuel on the way home.
This meant borrowing an empty fuel can from my brother-in-law, popping to a station to fill it up and then heading off to find him.
Subsequently his car developed a few problems which resulted in a £50 filter-cleaning bill.
How far can you drive with the light on?
"There's no statutory amount that should be left in the tank before the warning light comes on," says Matthew Minter from motor manual publisher Haynes. "But typically it's around 50 miles."
However Minter stresses that fuel gauges aren't always accurate and the capacity of the reserve tank varies among different models.
"Some modern cars can cut out without warning," adds Tony Rich, AA Patrol of the Year. "So don't leave it till you're running on fumes before filling up."
Get in the habit of thinking of the low-fuel light as a final warning, rather than driving around with it on.
Dangers of running on empty
"As the petrol level gets low you'll start picking up debris from the bottom of the tank," says Minter. "This can damage both the fuel filter and pump."
In the worst case, running out of petrol can cause the fuel pump to run dry which could mean a £200 garage bill.
"With modern diesel cars, the engine management system shuts down before you run out of fuel," says Minter. This prevents causing what could be thousands of pounds worth of damage to the vehicle.
But with petrol cars there's no system like this in place.
If you're running low with miles to go, fuel preserving tactics include driving with a very light foot and keeping to fifty miles per hour, providing this is within the speed limit, Minter adds.
'I'm too cheap to fill up the tank'
While thankfully I've never run out of petrol myself, I rarely fill up to the brim.
Psychologically I seem to have a cut-off point at around £35.
My car could easily hold double that amount but somehow I can't bear the thought of pumping £70 of cash into it, even if it means a repeat visit to the same petrol station a week later.
Sounds daft, I know, but that's just what I do.
Can driving with low fuel save money?
But does driving on a full tank cost more?
A full load could mean the engine has to work harder as the petrol weighs the car down.
But Minter says in reality any effect will be minimal.