Petrol pumps and the extra penny

dzug

goldspanners wrote: »

do the maths in a calculator,it comes to 25.00497.im guessing the pump rounds up to the next nearest full pence.you will find most retailers do this.
dont think im jumping to the defence of the retailer,just trying to point out what has hapened.

Well if you put 25.0349 in the calculator it comes out £25.009865 so you could only be losing out .000135 of a penny. And if you put 25.0399 in (that is assuming that the gauge doesn't click on until it actually gets to 25.04) then you've gained a fraction.

LuciferTDark

How does the speed of fuel being pumped out explain why the pump put extra money on after the OP stopped pumping?

vikingaero

If you suspect a dodgy pump then you can call Trading Standards who will sometimes check. They use traditional methods of brass jugs! They dispense fuel into these measured jugs and then pour it back into the main tanks. Even if a supermarket claims that the pumps are calibrated would you trust some part time surfer dude on the counter?

On another note I've filled up with say £20.00 of fuel. I've replaced the nozzle and the display on the pump says £20.00. But when I get into the kiosk the attendant tells me that it's £20.01p! I couldn't be bothered to argue the few times it has happened.

banger9365

so it's not just me getting the extra penny on the pump at asda,last time i used asda i stood at the pump and waited for it to change buy a penny it did not ,and when i payed guess what it was a penny more.
i also us morrisons/sainsbury's and theres do not do it ,put they have newer pumps than asda

Stephen_Leak

I've just had a fascinating chat with a very helpful and knowledgable "petrology officer" at my local council's trading standards office.

Firstly, they haven't received any previous complaints about that particular pump, but he took the details for possible future reference.

They have been expecting more complaints as the petrol price got higher and higher over recent months. At £1 per litre, one penny-worth of petrol is just 10 millilitres, or 2 standard medicine teaspoons. Not a lot.

Also, a digital display doesn't go up in a smooth and linear manner (like an old-fashioned dial) but jumps at each whole centilitre or penny. Therefore, if you are on the edge (which GS's calculations show that we are on the price display) it could quite literally only take an extra drop of petrol to trip the display.

Especially if the hose is getting a bit old and flabby (the technical term is "hose dilation"), even the petrol sloshing around in it as I walked back to the pump could easily have had the same effect.

The latest pumps are designed to measure the fuel with ever-increasing accuracy. The only problem with this is that it just makes them even twitchier!

I will never look at the humble petrol pump in quite the same way again.

kitchen_buff

My wife gets perol from Asda and she keeps telling me that when she gets to pay for the petrol it has gone up by a penny, I never took much notice of her before until I read this thread, this asda is in Bromborough, Wirral. I use Shell, same price as Asda but I collect Air Miles.

Stephen_Leak

I got some more petrol last night. I wasn't planning on using pump 5, but the car using it pulled away as I came up behind him and there was another car behind me, so I got stuck with it yet again.

This time, I stopped the delivery at £24.99 and the proverbial "bad penny" clicked over as I walked back to the pump again.

Stephen_Leak

Update: I got some more petrol, but at a different ASDA store. I aimed for £25.00 @ 99.9p per litre (BTW, all due respect to ASDA for keeping it below the £1 mark for so long) again, and it flipped over to £25.01 again.

Therefore, it clearly isn't a problem with one particular, badly calibrated pump. It is just down to the mathematics, now that the price per litre is so close to a round figure.

Next time shall aim for £30 and see what happens. I'll keep you posted.