Poor MPG with Tesco fuel

cardinalbiggles

mikey72 wrote: »

It's a pressure switch in the pump handle the senses when the tank in full. So if it's a diferent brand of pumps between asda and tesco, I can easily see the pump switching off for different heights of fuel in the filler pipe, and depending on flow rate the pressure change will be faster or slower as well which will affect the switch point.
If the asda nozzle is an inch loger, it's stop sooner.

But you'll have to list a few reasons why it won't be different for me then.

Yeah, ok you are telling me that your going on when the pressure switch cuts off and not brimming your tank, your having a girrafe now arent you?

Secondly, we are talking volumes here, the volume of fuel is controlled from a flow meter in the actual pump unit and takes into account the volume of fuel in the hose up to the nozzle. There will be very little margin for error in what is dispensed to you.

My advice, dont bleat on about mpg etc. etc. etc. until you actually brim your tank, its the only way to know accurately your consumption!

mikey72

cardinalbiggles wrote: »

Yeah, ok you are telling me that your going on when the pressure switch cuts off and not brimming your tank, your having a girrafe now arent you?

Secondly, we are talking volumes here, the volume of fuel is controlled from a flow meter in the actual pump unit and takes into account the volume of fuel in the hose up to the nozzle. There will be very little margin for error in what is dispensed to you.

My advice, dont bleat on about mpg etc. etc. etc. until you actually brim your tank, its the only way to know accurately your consumption!

So no reason you can come up with then.
The pump cuts off when it cuts off, or do you take the nozzle out of the tank and fill until it runs out of the filler and down the side of the car? Obviously carefully recording how much you spill each time?

LandyAndy

cardinalbiggles wrote: »

Yeah, ok you are telling me that your going on when the pressure switch cuts off and not brimming your tank, your having a girrafe now arent you?

!

You don't have much choice in the modern, petrol powered, cars I've owned. If you don't push the nozzle right into the filler neck the pump keeps cutting out.

I tend to fill to the click then count to five and fill to click again then repeat that one more time. 90% of the time I use the same pump at the same, Esso, filling station.

I avoid Tesco fuel because it tends to be more expensive.

mikey72

LandyAndy wrote: »

You don't have much choice in the modern, petrol powered, cars cars I've owned. If you don't push the nozzle right into the filler neck the pump keeps cutting out.

I tend to fill to the click then count to five and fill to click again then repeat that one more time. 90% of the time I use the same pump at the same, Esso, filling station.

I avoid Tesco fuel because it tend sto be more expensive.

Exactly the same method as I use.

Lum

Tesco's fuel is indeed 5% ethanol. Bio-ethanol to be precise.

That plus the absolute bare minimum additive package they can get away with can easily explain this difference.

The discussion of additives was done to death in the Mondeo vs Sainsburys thread though, not really much point bringing it up again.

somech

question for the op
when filling your car do you note how many litres of fuel you have purchased ?

Captain_Proton

somech wrote: »

question for the op
when filling your car do you note how many litres of fuel you have purchased ?

Yes, that and the car's mileage upon filling. When I next re-fill I can use the miles since the last fill and the volume of the new fill to calculate my MPG, since the current batch of fuel is replacing what I used since the last fill.

Basically MPG on last batch of petrol = (current fill mileage - last fill mileage) / gallons of fuel inserted in current fill.

Have been doing this for years, it helps me monitor how the car performs economy wise on certain drives, and it makes it easy to spot if there is a problem with the engine.

As a side note, when I took the car to France and drove on the autoroutes, I got a whopping 50mpg from it, presumably due to the very smooth road surface and the steady speed that can be maintained on the quiet roads.

flashnazia

All those who say tesco fuel is the same as any other- then why did tesco come off the worst for the bad fuel fiasco some years ago?

I agree with the op, I too noticed reduced mpg with tesco fuel.

cardinalbiggles

Lum wrote: »

Tesco's fuel is indeed 5% ethanol. Bio-ethanol to be precise.

As are most unleaded fuels, its the max they can get away with until all the fibreglass storage tanks are replaced back to other materials again as at 6% it starts to melt them.

Captain_Proton

cardinalbiggles wrote: »

As are most unleaded fuels, its the max they can get away with until all the fibreglass storage tanks are replaced back to other materials again as at 6% it starts to melt them.

I have read that many cars made in recent years can cope with large amounts of ethanol in their fuel, like 85% ethanol to 15% petrol (E85 as its known). This is because they have a computerised management system with sensors that can regulate the fuel to burn at the correct rate. Perhaps Tesco fuel gives better mpg in these vehicles than in my old, more basic car.

My Fiesta was designed in the days when unleaded was unleaded petrol and nothing else. It probably wouldn't cope with a high proportion of ethanol in the fuel since it was never designed for it. I made a point of avoiding E10 (10% ethanol) fuel in France for this reason - I didn't want the fuel system to melt 700 miles from home!

It would be interesting to try to run a banger on 100% ethanol, it's just a pity that this is a hanging offence in the UK. For now...