What you get in will give you a good idea, I think I'm right that you keep a close check on fuel economy so will always brim in the same manner, the mpg calculation since the last fill up including and not including the 7 litres will tell you exactly what happened.

 

Were you to actually run your car out (not recommended on a common rail system) then you would find that can get in a lot more than when you fill up thinking the tank is empty, minimum 5 litres probably 7. However thats neither here nor their in termsof whether you filled with air and not diesel.

In my experience of driving both diesel and petrol Skoda's over the last 15 years and 180,000 miles when I get down to 5 miles range on the computer I can actually get another 15-20 miles from the fuel (normally between 1.2-1.7 litres actually left).

Have you ever actually run it dry or are you estimating the remaining fuel on how much you put in when you brim?

 

My experience over 15 years and about the same mileage (only 2 vehicles) is that there is a lot more remaining than you would think and I have run out several times, however with an early mechanical injection engine and a PD one its no drama to run dry, I definitely wont be doing it with the Yeti so will never actually be able to use the full range.

 

ran out many times on the MK1 Octavia due to a dodgy fuel sender sticking and on the MK2 I did it deliberately as soon as I got it.

Any second now someone will post some daftness about sucking up crap out of the bottom of the tank if you let the level get too low.

 

@shyVRS245it would be worth popping back to that pump tomorrow if your refill calculations support  your nothing dispensed idea; see if it has an out of order sign...

After driving 527 miles and a blizzard blowing decided to pull off the Motorway and put £20 of cheap 95 octane Sainsbury’s fuel with only 15 mile range left. Not worth the gamble and as soon as I started the engine the fuel gauge shot out of the red zone and range jumped to 215 miles with 16.8 litres put in. Tesco’s now in 2 days before my voucher expires. Photo taken after leaving the Shell garage 25 miles earlier.

50 minutes ago, Wino said:

Any second now someone will post some daftness about sucking up crap out of the bottom of the tank if you let the level get too low.

 

@shyVRS245it would be worth popping back to that pump tomorrow if your refill calculations support  your nothing dispensed idea; see if it has an out of order sign...

That's the plan Wino as I have to pass it on the way to work so I will pull up to it buy no fuel and ask for my £10 back and see what response I get directly to my face.😉

So range shot up by 200 miles for 16.8 litres which means the average fuel consumption is expected to be 54.2 mpg

 

💹 Another Shy record!!! Yahoo!!! Congratulations!!!

 

Or did it shoot up by 200 miles for (16.8 + 7) litres which is an expected consumption of 38.2 mpg......dohh...

 

So the 7 litres have finally come out of hiding....or Sainsbury's gave you 7 litres too much fuel...🤔

 

As I tried to explain earlier (not that shy will listen anyway) a tiny refill causes only a small deviation at the (relatively sticky) fuel level sensor which the computer dismisses as variation due to inclination, fuel slopping, stiction, temperature/pressure/evap system, shy's body weight causing the car to lean etc. etc 

 

The fuel gauge is not driven directly by the sender but by an algorithm. The alternative would be a fuel gauge that moves nervously to full or empty everytime you brake, turn or go up a hill.

 

Next, your water temperature gauge, is it really exactly 90 deg C constantly in your engine?  Really? Discuss......

 

 

Edited 25 February, 20206 yr by xman

21 minutes ago, shyVRS245 said:

That's the plan Wino as I have to pass it on the way to work so I will pull up to it buy no fuel and ask for my £10 back and see what response I get directly to my face.😉

 

If I were on the till I'd show you the computer record, and if you still argue/threaten then call the police (press the button under the counter). Not sure if simply being stupid is an arrestable offence though 😉

A fuel sender will never be linear or accurate at the top or bottom of its stroke, that said the VAG ones are remarkably good but there is definitely an algorithm to create this "virtual" (better phrase) reserve capacity of around 7 litres, it absolutely does what Shy experienced and I have seen it first hand many times, absolutely definitively when i ran out, put 5 litres in to see 40 miles range appear to then drop to zero after 2km.

 

And yes, the figures he has given prove conclusively mathematically that he did recieve the 7 litres, shame he didnt fill the tank completely because I think even he would have realised then.

 

Regarding the algorithms, its well documented and generally accepted by most that the temperature guage will read precisely 90°c without the slightest variation when the actual temp shown in VCDS varies as much as it would in any other vehicle according to speed, engine load, heater settings, outside air temp etc, it only deviates when outside of the programmed limits.

I'd never trust a sender on such a small top up quantity having done it on a few occasions because the price of fuel in Adelaide (South Australia) can vary by up to 30% over a varying (2 to 3 week) price cycle and up to 50% when comparing remote regional to urban pricing.

 

In terms of dispensing accuracy I have had one incident where the pump over dispensed by about 25% (confirmed by an unexpectedly good calculated consumption figure AND separate 5 litre jerrycan only taking 4 litres). Conversely I have had only one incident where I truly suspected an under amount dispensed (really poor calculated consumption figure for no apparent reason). Both incidents were months apart and at different stations but the same brand.

 

The fuel tank on most VW group medium to large cars seem to have a working fuel capacity 5 litres or so more than the published figure. This is not to be confused with the fuel gauge accuracy or low level warning indicators, the performance of which varies considerably from car to car.

 

With the very high pressures now used in diesel and petrol injected engines I would recommend avoiding the potential damage and wear caused by running out of fuel.

 

BACK ON TOPIC  

I think that @Rockinghorse should consider rejecting the car if it is still an option. 

 

 

Edited 25 February, 20206 yr by Gerrycan

I had a 2010 Euro 5 Toyota iQ.  The fuel tank capacity was only 32 litres so the same as a Skoda Citigo.

If you put in petrol when the reserve light came on it required to be 11 litres or more or the car did not recognise that you had put in any. 

 Obviously it did keep running and knew the tank was not empty.

 

UK Weights and measures and the HMRC are pretty hot on what you are sold and taxes / duty paid. 

Fuel pumps are not giving out free fuel which is cheap / the taxes are not, but then the filling station pays the Tax as the Tanker delivers the fuel to the filling station.

UK weights and measures and taxes comes down to a measure of alcohol as well.  No more putting a sixpenny piece in the bottom of a measure.

Edited 26 February, 20206 yr by Roottootemblowinootsoot

13 hours ago, shyVRS245 said:

£20 of cheap 95 octane Sainsbury’s fuel with only 15 mile range left. Not worth the gamble and as soon as I started the engine the fuel gauge shot out of the red zone and range jumped to 215 miles with 16.8 litres put in

I'd expect that given the volume, and the low end of midscale amount of fuel now in the car. The slow reactions happen near the ends (both ends) of the scale.

On the general weights and measures point, my mate ran a filling station. He had a calibrated 5 (real, not US) gallon drum used for checking pump calibration. Taking 4.5l  to the gallon (approximation but makes numbers easier), this means that his calibration checks were over 22.5l delivered.

@KenONeill

What a load of P1ss.  Un-calibrated p!ss.   

4.5461 litres to an imperial gallon.   Customers might think of 2 gallons as 9 litres. for easiness.  

 

5 gallons is 22.73 litres.

 

If the tanker fills your stations tanks with 10,000 litres and you pay Tax / Duty on that fuel then sell it you want your calibrations exact. 

The Customers are charged the Tax & Duty.

 

Mony a mickle maks a muckle. 

You can not go giving away even an extra tenth of a litre to every customer filling a car, or worse still a van or lorry.

Underselling is criminal.  Likely not a court action though, a HMRC penalty.  As in we reckon you have deprived the treasury of £???? whatever.

They worry more about the treasury than the customers though.

Edited 26 February, 20206 yr by Roottootemblowinootsoot

23 minutes ago, KenONeill said:

On the general weights and measures point, my mate ran a filling station. He had a calibrated 5 (real, not US) gallon drum used for checking pump calibration. Taking 4.5l  to the gallon (approximation but makes numbers easier), this means that his calibration checks were over 22.5l delivered.

 

11 minutes ago, Roottootemblowinootsoot said:

@KenONeill

What a load of P1ss.  Un-calibrated p!ss.   

4.5461 litres to an imperial gallon.   Customers might think of 2 gallons as 9 litres. for easiness.  

 

5 gallons is 22.73 litres.

 

If the tanker fills your stations tanks with 10,000 litres and you pay Tax / Duty on that fuel then sell it you want your calibrations exact. 

The Customers are charged the Tax & Duty.

 

Mony a mickle maks a muckle. 

You can not go giving away even an extra tenth of a litre to every customer filling a car, or worse still a van or lorry.

Underselling is criminal.  Likely not a court action though, a HMRC penalty.  As in we reckon you have deprived the treasury of £???? whatever.

They worry more about the treasury than the customers though.

Is the fact that I used an approximation for ease of calculation now clear enough to suit you?

@KenONeill  I thought you meant the mate was using they rather inaccurate calculation. 

So it was just you. 

 

Does the mate still run a filling station by any chance?  Or was it closed down decades ago?

This is another slant on fuel consumption which has probably been aired previously but I'd like to have my "fourpenneth".

 

Below is an extract from my Superb handbook:

 

■ Unleaded petrol that has a higher octane number than that required by the
engine can be used without limitations.
■ The use of petrol with an octane rating higher than 95 RON does not result
in either a noticeable increase in power nor lower fuel consumption in vehicles
for which unleaded petrol 95/min 92 or 93 RON is specified.
■ On vehicles using prescribed petrol of min. 95 RON, the use of petrol with a
higher octane number than 95 RON can increase the power and reduce fuel
consumption.

 

The sticker on the fuel flap of my car states I should use min.95 RON and the third bullet point above states if I use higher octane petrol it could increase power and reduce fuel consumption. This seems to be supported by the oil companies, well at least one of them. Below is an extract from the Esso website:

 

What is the difference between regular and premium petrol?

 

As well as having a higher octane (which helps to reduce knocking-related performance losses in modern cars), our Synergy Supreme+ Unleaded fuel has extra additives which can benefit all petrol cars, even older ones. Making it our best ever protection for your engine.

Synergy Supreme+ Unleaded fuel has double the amount of detergent additive compared to our regular petrol, which helps give your engine a deeper clean. The cleaner your engine, the better it can perform and the more fuel efficient it is.

Synergy Supreme+ Unleaded fuel also contains molecules that help to reduce friction and prevent wear and tear in your engine.

 

Looks to me like good reasons to use the premium petrol, assuming you can afford it?

 

 

 

4 minutes ago, MASKO said:

This is another slant on fuel consumption which has probably been aired previously but I'd like to have my "fourpenneth".

 

Below is an extract from my Superb handbook:

 

■ Unleaded petrol that has a higher octane number than that required by the
engine can be used without limitations.
■ The use of petrol with an octane rating higher than 95 RON does not result
in either a noticeable increase in power nor lower fuel consumption in vehicles
for which unleaded petrol 95/min 92 or 93 RON is specified.
■ On vehicles using prescribed petrol of min. 95 RON, the use of petrol with a
higher octane number than 95 RON can increase the power and reduce fuel
consumption.

 

The sticker on the fuel flap of my car states I should use min.95 RON and the third bullet point above states if I use higher octane petrol it could increase power and reduce fuel consumption. This seems to be supported by the oil companies, well at least one of them. Below is an extract from the Esso website:

 

What is the difference between regular and premium petrol?

 

As well as having a higher octane (which helps to reduce knocking-related performance losses in modern cars), our Synergy Supreme+ Unleaded fuel has extra additives which can benefit all petrol cars, even older ones. Making it our best ever protection for your engine.

Synergy Supreme+ Unleaded fuel has double the amount of detergent additive compared to our regular petrol, which helps give your engine a deeper clean. The cleaner your engine, the better it can perform and the more fuel efficient it is.

Synergy Supreme+ Unleaded fuel also contains molecules that help to reduce friction and prevent wear and tear in your engine.

 

Looks to me like good reasons to use the premium petrol, assuming you can afford it?

 

 

 

Indeed before my recent remap using 99 octane Tesco Momentum Skoda claim 268bhp for my Superb 272 yet it actually produced 283bhp (15bhp more) and torque was up from the claimed 350nm to 369nm on a completely standard car. Before the remap it averaged 38.9mpg  a very good result compared to the 39.8mpg Skoda claim using regular 95 octane fuel on the NEDC testing regime.

@MASKO  Higher octane fuel can be lovely.  As to the extra detergents maybe not so with a TSI.

 

You have the VW504 / 507 or VW 508 /509 Long Life oil and the cleaning properties / additives.

 

Maybe use Higher Octane fuel and VW 502 so 5w 30 FS oil and do fixed services,  No long life oil but long lived engines and no 'Bore wash' issues as TSI's from the last generations have had.

 

Esso Synergy produced in the UK by Greenergy that produces Tesco Momentum 99 and who are part owned by Tesco, and who are partners with Royal Dutch Shell for importation and storage of base fuels to the UK.

 

These amazing Additive packages added to 97 ron or 99 ron in the UK are not that special.  Give us the extra ethanol.

 

PS

'Premium petrol' seems to be lost in Translation.  'Premium priced'    As to Tesco Momentum the premium paid might be less than £2.50 a tank over 95 ron supermarket unleaded, 

& no more over Shell, BP, ESSO, Texaco, Gulf etc 95 unleaded.

 

You get Premium Diesel in the UK. 

& you get 95 ron minimum Unleaded,

or Super Unleaded. & Super Unleaded in the UK comes as 97 ron minimum like Esso Synergy Supreme Plus, BP, Sainsburys etc 97 octane.

You need Tesco Momentum 99 or Shell V-Power Nitro + if you are after 99 ron minimum in the UK.

Edited 26 February, 20206 yr by Roottootemblowinootsoot

30 minutes ago, MASKO said:

This is another slant on fuel consumption which has probably been aired previously but I'd like to have my "fourpenneth".

 

Below is an extract from my Superb handbook:

 

■ Unleaded petrol that has a higher octane number than that required by the
engine can be used without limitations.
■ The use of petrol with an octane rating higher than 95 RON does not result
in either a noticeable increase in power nor lower fuel consumption in vehicles
for which unleaded petrol 95/min 92 or 93 RON is specified.
■ On vehicles using prescribed petrol of min. 95 RON, the use of petrol with a
higher octane number than 95 RON can increase the power and reduce fuel
consumption.

 

The sticker on the fuel flap of my car states I should use min.95 RON and the third bullet point above states if I use higher octane petrol it could increase power and reduce fuel consumption. This seems to be supported by the oil companies, well at least one of them. Below is an extract from the Esso website:

 

What is the difference between regular and premium petrol?

 

As well as having a higher octane (which helps to reduce knocking-related performance losses in modern cars), our Synergy Supreme+ Unleaded fuel has extra additives which can benefit all petrol cars, even older ones. Making it our best ever protection for your engine.

Synergy Supreme+ Unleaded fuel has double the amount of detergent additive compared to our regular petrol, which helps give your engine a deeper clean. The cleaner your engine, the better it can perform and the more fuel efficient it is.

Synergy Supreme+ Unleaded fuel also contains molecules that help to reduce friction and prevent wear and tear in your engine.

 

Looks to me like good reasons to use the premium petrol, assuming you can afford it?

 

 

 

 

Came across this video from a Fifth Gear episode in 2016.

 

 

Check out those 2016 fuel prices from not quite 4 years ago.

 

 

7 minutes ago, Apprentice said:

 

Came across this video from a Fifth Gear episode in 2016.

 

 

Check out those 2016 fuel prices from not quite 4 years ago.

 

 

Wow only 4 years ago nearly £1.36 per litre for Asda unleaded. Paying just under £1.27 per litre for 99 octane Tesco Momentum now in Feb 2020.

Shell V-Power was 98 ron minimum back then,

it changed to 99 ron minimum when re-launched as 'Shell V-Power Nitro+'.

Also the Golf GTi tested was registered in 2012 and fuel injection and engine management systems have moved on a fair bit since then witness the Mercedes AMG A45 S which now produces 415bhp and 500nm of torque from just 2.0 litres.

Horses mouth.

http://volkswagen.co.uk/need-help/need-help-faqs/owners/Fuel

 

Quick update e-mail received from Shell UK regarding my complaint yesterday morning and although they claim the pump is regularly tested and not faulty they will send me a £5 voucher as a goodwill gesture. Couldn't double it to £10 and admit any liability.