The Student Room Group

Reply 1

when you say 2 hours? What speed/how far?

Cant you work out the miles per gallon? That would give a more accurate figure.

Reply 2

Yeah no point being so random about it, probably isn't a problem but only way you will know is by calculating MPG or using a trip computer (if present).

Reply 3

how do u calculate miles per gallon? thx.

Reply 4

Do the following:

Fill up your car at a certain petrol station, remember which. Fill it up until the pump clicks off, once.

Reset your trip meter on your dashboard so it zeros.

Drive until the tank is about one quarter full.

Go to the same petrol station (same pump if possible)

Once again, refill the tank until the pump clicks off, once. Record number of miles completed to this point and the number of litres you have put in to fill your car on this occasion.

Take the number of litres and divide it by 4.546, that's your number of imperial gallons used. Divide your number of miles (say 300) by the number of gallons (say 10), 300/10 = 30 MPG.

Hope that helps.

Reply 5

street
how do u calculate miles per gallon? thx.


One way is to fill your tank to the very top and then record how many miles you do and fill up the tank again. Only problem it costs a fortune to fill tank and some might spill out when you go round a corner.


Deliberatly run out of petrol . Put one gallon into your tank and run the car until it runs out of petrol again. The distance travelled tells you how many miles you have done on the one gallon.

Reply 6

The 1 gallon method wont give you a very reliable method- will depend heavily on your driving during that short time, whereas a full tank to quarter will give you a more realistic average

Reply 7

It costs you no more to fill your car to the top every time than it does to fill it up 4 times by a quarter each go....hence assuming you will ever drive your car again after filling your tank, it's an investment in fuel, if nothing else.

I fill up every single time, why? Because it takes time and effort to go to a petrol station so why in the world would I do it more often than necessary. Car petrol pumps and car petrol tanks do not allow petrol to spill out...

NEVER deliberately run out of petrol, that's VERY bad advice. Do not follow the above.

Reply 8

How many miles was 2 hours?

2 hours down the M6 at 130mph and no wonder it's ran out

Reply 9

Agreed. The price of fuel will vary by a few pence max. over the time taken to use 1 tank of fuel.

The only time I dont fill up at a station in when I know Iwill be driving to a bigger town, where i know i can get fuel significantly cheaper, so will stick a fivers worth in.

Reply 10

cRaig
The 1 gallon method wont give you a very reliable method- will depend heavily on your driving during that short time, whereas a full tank to quarter will give you a more realistic average


If you want an accurate figure it won't be any good relying on the tank being a quarter full. Petrol gauges are very inaccurate.

Reply 11

steve2005
If you want an accurate figure it won't be any good relying on the tank being a quarter full. Petrol gauges are very inaccurate.


You don't understand the full tank method do you.

Reply 12

Ryan
How many miles was 2 hours?

2 hours down the M6 at 130mph and no wonder it's ran out

or if the op decided to drive in 2nd gear all the time!

Reply 13

Would just like to second that running the fuel tank till its empty is a very silly thing to do. Worst case scenario the pump will suck up some crud and clog up your fuel rail and injectors.