Like most modern cars, mine contains a small computer which attempts to tell me how much petrol I have and how far I can drive before it all runs out. I’ve always been intrigued just how far I can get before the engine stops, it’s something handy to know when miles from the nearest petrol station too.
Last night I forgot to fill my car with petrol and this morning my car told me it had 27 miles of fuel remaining. I was late for work and based on previous experimentation knew I had enough to at least get to work. A 16 mile journey with 27 miles of fuel should be fine.
It was a bit ominous passing the last petrol station for six miles with the petrol meter saying 18 miles left. I put my foot down to go up a hill and was immediately told “—” miles left. I’m not entirely sure how the petrol meter works, but it’s evidently taking an average of the current MPG and some estimations programmed into it because rolling down the other side of the hill told me I once again had 18 miles left, and was doing an amazing 999.99MPG.
I made it to work fine, with a fuel meter telling me “—” miles left. The nearest petrol station was two miles away and I made it without incident, but really curious just how empty the tank was. From looking at Google Maps I’d driven six miles to work with the gauge saying “—” and a further two to the petrol station.
My car took 41 litres of petrol to fill it, before the pump’s cutout activated. I didn’t try to top the tank off and assume the pumps stop delivering fuel when liquid blocks the small hole in the end of the nozzle. According to the car’s handbook it has a fuel tank with an approximate capacity of 47 litres.
So I had six litres left and nothing to worry about really? maybe… probably not though. My car does, on average 40MPG which is the same as approximately 10 Miles per litre. My car told me I had 27 miles left which converts to around three litres of fuel. Except it stopped telling me how much was left after only ten miles of travelling. And then I drove a further six miles to work and two more to the petrol station.
The car will be programmed to err on the side of caution, with an unknown reserve to stop idiots like me getting stranded by the roadside. So according to the petrol station and car’s handbook I had six litres remaining which would have got me a further 8 miles approximately. However according to some very average maths I set off this morning with just three litres of fuel.
I’m guessing I rolled into the petrol station with less than half a litre of petrol remaining, probably a dribble in the bottom of the tank and whatever is in the fuel lines and filter.
41 litres of petrol cost me 48 quid 🙁