Tesco / Morrisons contaminated Petrol

[pammy]

This story has just been on the BBC 6 o'clock news. Seems the petrol was in the system a couple of weeks ago so it hasn't just happened today.

Sounds horrendous though.

 

[Satch]

Story from last year

Moreover, adding bioethanol to petrol means oil companies will have to, for the first time, start worrying about water getting into their equipment. "Normally, water from condensation or wherever collects at the bottom of tanks and you can remove it. But alcohol and water mix exceptionally well, which leaves you in the uncomfortable situation of having gasoline with a mixture of water and alcohol sloshing around," says one industry expert who preferred to remain anonymous.

http://www.guardian.co.uk/climatechange/story/0,,1710291,00.html

One year on:

Mark Peacock, Service Manager at Mercedes-Benz in Watford, said 15 cars with fuel problems have come through his service department in the last four days.

'It's terrible,' he said. 'The number of cars coming in is unbelievable - all of them have fuel that has been contaminated. Half of them came in after they refuelled at Tesco down the road. We don't know whether it is water or something else, but it is clear there is a problem.'

Mechanics at Mercedes have had to flush out the fuel tanks and fuel lines and then replace the oxygen sensors on all the cars suffering from contamination. Customers are paying between £800 and £1000 for the repairs.

'We've had reports from other dealerships as well as independent garages,' added Peacock. 'It's a shame for the customers, because their warranties do not cover this sort of thing.'

http://www.whatcar.com/news-article.aspx?NA=224327

 

[shadowninja]

and are tescos still serving tesco value petrol?

 

[Satch]

I know in the UK 5% ethanol is the standard but the same must happen.

The situation is different for gasoline oxygenated with 10 vol % ethanol. The gasoline-alcohol blend can dissolve more water (6000–7000 ppm at 21°C/70°F). When this blend is cooled, both the water and some of the ethanol become insoluble. Contacting the blend with more water also draws ethanol from the blend. The result, in both cases, is two layers of liquid: an upper ethanol-deficient gasoline layer and a lower ethanol-rich (up to 75% ethanol) water layer. The process is called phase separation and it occurs because ethanol is completely soluble in water but only marginally soluble in hydrocarbons.

After phase separation, the gasoline layer will have a lower octane number and may knock in an engine. The fuel also is less volatile. The engine will not run on the water/ethanol layer.

As the concentration of ethanol is decreased, the aromatics content of the gasoline is decreased, and as temperature is decreased, less water is required to cause a phase separation.

The potential for phase separation requires that gasoline oxygenated with ethanol not be exposed to water during its distribution or use in a vehicle. Because of this requirement, gasoline oxygenated with ethanol is not transported in pipelines, which sometimes contain water. Rather, the ethanol is added to tanker trucks at the terminal immediately before delivery to the service station.

Housekeeping at the service station is very important to prevent water contamination.

This water sensitivity also means that extra care should be taken when gasoline oxygenated with ethanol is used as a fuel for boat engines. Ethanol blends are hygroscopic (absorb moister from the air) and in time can phase separate during storage if the tank is vented to the atmosphere and is subject to breathing as a result of temperature changes.

http://www.chevron.com/products/prodserv/fuels/bulletin/motorgas/4_oxygenated-gasoline/pg2.asp

T

 

[glojo]

How comes every petrol car that has refuelled at these stations has not suffered?

I have no reason to disbelief this but when a scare gets broadcast then everyone seems to be effected.

I am merely being inquisitive here and get a better understanding.

Regards,
John the inquisitive

 

[mb240]

Is this just media hype or is it worth staying clear of Tesco and Morrisons fuel for a while?

Anyone know what is causing the problem?

Anyone broken down yet?

I have no idea if it's worth staying away now, but my own experience of misfiring two weeks ago after a Tesco fill in Dublin (Dundrum station) will mean I never go there again, and after it happened I read many stories online of people developing problems.

Someone on Pistonheads mentioned about Tesco using more bioethanol in the fuel? I don't really understand it, but in any case, I learned my lesson a few weeks ago, and am not surprised really. It is entirely dubious.

Also, I will be getting Heinz beans from now on, and not Tesco beans. :bannana: :bannana:

 

[GRAV888]

Somebody after compensation, or has it reached diesel now too?
Found the following in the link posted earlier in the thread:

The oxgygen sensor of my Peogueot 406 HDi stopped working after using contaminated fuel from a Tesco petrol station in Bedford. It cost over £300 to repair!
Shafi Khan, Bedford, England

 

[Subyland]

I am glad to have read this as I nearly filled my car up at Tesco today. I'll go to Total tomorrow. !!

 

[big x]

Funnily enough I was about to post something about how good UK fuel was !
I sawed a fuel filter in half that was 7 years old and had done 130k.The internal filter is very similar to an oil filter in construction, a corrugated paper mesh.Although slightly stained it was not blocked and still serviceable although well past it's replacement date.In fact some cars now come with fuel filters that are supposed to be sealed for life and never need changing !
The dodgy fuel seems to be coming from the company Greenergy, a pretty big clue that it's something to do with the ethanol mix or tank cleaning process.

adam

 

[DITTRICH]

An educational, if somewhat depressing thread. Supposing a difference of 3p per litre and an average refuelling of 50 litres you save £1.50 per session at the supermarket. This equates to around 650 trips to the supermarket fuel station before you save enough to pay for say £1,000 of repairs. How often do these fuel incidents occur and what are the chances of being caught out? Personally, I now visit the supermarket fuel station around 3 times per month on average so I'll save £1k over around 18 years. Am I likely to get caught out at least once in 18 years? Well I've gone 8 years without an incident of this nature and I've only been driving for 8 years in the UK. I don't use Tesco or Morrisons but until this incident quietens down, I shall use a regular branded petrol station unleaded for the next 2 weeks or so as a precaution. Invest a fiver to avoid a possible £1k bill. Seems reasonable to me. And before people take issue with the figures - they are all ballpark figures for illustration - not an exact calculation.
Les
Just seen on the web...
http://www.greenergy.com/home/Fuel_quality_statement.pdf

 

[GrahamC230K]

I use Tescos Super as it was prior to Shell V-Power the only 99RON fuel available and mated well the highly avanced timing on my tuned car. This could have been an Esso product sold at a premium rate for all I care I would still have been buying it. My nearest Shell station is also several miles away out of my home town.

It appears Greenergy are the supplier for both Tesco regular and Super unleaded.

Part of me wants to steer clear part of me wants o return knowing I have used the same petrol for the last 3800 miles, although I have not refuelled for over a week.

With no one admitting the ethanol content has changed or that the ethanol content has produced another unwanted effect, I am none the wiser really.

None of the reports I have read differentiate or even specifically mention which of the fuels are affected. Clearly not all cars have been affected. Some reports are adament the problem is the South others have reports from the north of England.

The latest I read on the BBC was an article claiming the fuel was within regulations and fine, followed by a statement from someone else that there was a poor batch. The facts could not be much less clear!

 

[saorbust]

I know in the UK 5% ethanol is the standard but the same must happen.

The situation is different for gasoline oxygenated with 10 vol % ethanol. The gasoline-alcohol blend can dissolve more water (6000–7000 ppm at 21°C/70°F). When this blend is cooled, both the water and some of the ethanol become insoluble. Contacting the blend with more water also draws ethanol from the blend. The result, in both cases, is two layers of liquid: an upper ethanol-deficient gasoline layer and a lower ethanol-rich (up to 75% ethanol) water layer. The process is called phase separation and it occurs because ethanol is completely soluble in water but only marginally soluble in hydrocarbons.

After phase separation, the gasoline layer will have a lower octane number and may knock in an engine. The fuel also is less volatile. The engine will not run on the water/ethanol layer.

As the concentration of ethanol is decreased, the aromatics content of the gasoline is decreased, and as temperature is decreased, less water is required to cause a phase separation.

The potential for phase separation requires that gasoline oxygenated with ethanol not be exposed to water during its distribution or use in a vehicle. Because of this requirement, gasoline oxygenated with ethanol is not transported in pipelines, which sometimes contain water. Rather, the ethanol is added to tanker trucks at the terminal immediately before delivery to the service station.

Housekeeping at the service station is very important to prevent water contamination.

This water sensitivity also means that extra care should be taken when gasoline oxygenated with ethanol is used as a fuel for boat engines. Ethanol blends are hygroscopic (absorb moister from the air) and in time can phase separate during storage if the tank is vented to the atmosphere and is subject to breathing as a result of temperature changes.

http://www.chevron.com/products/prodserv/fuels/bulletin/motorgas/4_oxygenated-gasoline/pg2.asp

T

That last para is very interesting. All tanks are ventilated on UK forecourts - or they used to be. I wonder if this is a delayed effect, which is being magnified by a smaller error at the tanker depot......

 

[grober]

How comes every petrol car that has refuelled at these stations has not suffered?

I have no reason to disbelief this but when a scare gets broadcast then everyone seems to be effected.

I am merely being inquisitive here and get a better understanding.

Regards,
John the inquisitive

Could be a storage/ fuel composition interaction-- higher alcohol content fuel---not a problem in itself----- BUT if put into a tank which hasn't been properly drained/ cleaned of water---- BIG PROBLEM. Again very difficult to prove what the exact cause is. Might be humidity dependant. During cold weather theres not a lot of moisture in the air but during a mild spell more tank condensation?? Maybe the first folks getting their fuel after the filling station tanks was first filled would be OK since the interaction between water and the fuel would take time. Could be dealing with some complex chemical reaction kinetics here. Lets hope either Tesco/ Morrisons or the Petrol Suppliers "step up" and compensate the owners. Under the circumstances if my car was effected I would certainly want to keep all receipts and a sample of the tank contents in a suitable sealed container if the car petrol system needed drained.

 

[Satch]

Problem could also arise if car has some water in tank. WIth 100% hydrocarbon petrol not a problem because it sits at the bottom of the tank in an area designed to hold crud and water residues. But dump in ethanol/hydrocarbon fuel and water it is taken up into solution.

The water/alcohol takes up a lot of the additives and leaves reduced octane fuel behind

Note that one of the dewatering techniques used for fuel systems is to flush tanks & pipes with absolute alcohol!

If the makers claim there is absolutely nothing wrong with the fuel and that is true, then it has to be an extrinsic cause to create such a problem in so many cars.

I cannot think of a more common nor more available one than water.

 

[glojo]

I understand what folks are saying but how many cars an hour pass through a busy Tesco, or Morrison outlet? If we only say 4 per minute, then that is 240 an hour, multiply that by say 12 hours, then we are looking in excess of 2800 cars per single garage?

Clearly there appears to be some sort of problem, but I simply cannot get my head around the alleged issue.

If there is a problem then why on earth keep selling the fuel? In this modern age of litigation these companies are leaving themselves wide open IF there is still contaminated fuel in their tanks (the suppliers)

Regards,
John the curious

 

[saorbust]

I understand what folks are saying but how many cars an hour pass through a busy Tesco, or Morrison outlet? If we only say 4 per minute, then that is 240 an hour, multiply that by say 12 hours, then we are looking in excess of 2800 cars per single garage?

Clearly there appears to be some sort of problem, but I simply cannot get my head around the alleged issue.

If there is a problem then why on earth keep selling the fuel? In this modern age of litigation these companies are leaving themselves wide open IF there is still contaminated fuel in their tanks (the suppliers)

Regards,
John the curious

John,

typically in a petrol staton all the pumps are not served from single tanks - usually they have between 8-10 tanks of various sizes and grades of fuel.

I suspect - that given the trading standards actions - its likely the pumps which are serving the fuel from the tank(s) in questions are locked off - this wouldn't preclude them selling say diesel from the same pump - its a different tank.

I wouldn't run a garage and not lock the pumps off - the risk is too great.

J.

 

[glojo]

John,

typically in a petrol staton all the pumps are not served from single tanks - usually they have between 8-10 tanks of various sizes and grades of fuel.

I suspect - that given the trading standards actions - its likely the pumps which are serving the fuel from the tank(s) in questions are locked off - this wouldn't preclude them selling say diesel from the same pump - its a different tank.

I wouldn't run a garage and not lock the pumps off - the risk is too great.

J.

I understand what your saying and hopefully I kept my figures on the conservative side?

I don't understand your point about using separate tanks, are you suggesting that Tesco, or Morrison use different fuel suppliers? Surely if the delivery tanker has a lorry load of alleged contaminated fuel, does it matter if this fuel goes into one tank or several?

I have read reports that the alleged delivery was confined to just two forecourts, but this then leads me to think the refinery is accepting responsibility.

 

[GrahamC230K]

Where did you read that John?

I'm not sying people don't travel up and down the country but if it were only 2 garages affected a lot of epeople are jumping on the bandwagon!

 

[Stratman]

It won't affect all cars, only those with clever fuel injection systems. Older cars with carberrytooters might splutter a bit but they should still run. Listening to the 'experts' on the radio it seems that the ethanol is destroying the lambda sensor and this in turn either makes the ECU give up and stop, or try to make the mixture correct despite the erroneous information which results in a seriously incorrect fuel/air ratio.

 

[saorbust]

I understand what your saying and hopefully I kept my figures on the conservative side?

I don't understand your point about using separate tanks, are you suggesting that Tesco, or Morrison use different fuel suppliers? Surely if the delivery tanker has a lorry load of alleged contaminated fuel, does it matter if this fuel goes into one tank or several?

I have read reports that the alleged delivery was confined to just two forecourts, but this then leads me to think the refinery is accepting responsibility.

Seperate tanks under the ground at the garage.

The law limits the physical size and the quantity of fuel a garage is allowed to keep as stock. Typically its in litres - about 500,000 is not abnormal. We used to have 33,000 litre tanks underground - 11 of them. 3 contained Diesel, 3 contained 4 Star, 4 Unleaded, 1 Super. Shows you how old it was.

Part of the reason for the tanks is to avoid them running dry (dregs, at the bottom), and also to avoid putting too much in case of contaiminants. You'll note the size is also the maximum amount that can be carried by one tanker - this is done by design. Its also bloody heavy and requires a lot of re-enforcement to be stored.

Most forecourts follow these rules - the grades of fuel and quantities may have changed, but broadly speaking its as above. There is also a limit on the number of pumps served product by any one tank - for example in our case the 4 unleaded tanks each served two pumps - making 8 dispensers for unleaded served equally by 4 tanks. It meant we could identify the most popular pump as well (no 8 - centre right side).

Anyway so my point is this - if the fuel had been contaminated, then it would be very easy for the garage to stop serving fuel from that source by simply closing off the pumps which serve the product from the related tank. But this would not prevent them from being open - they can serve from other nozzles.

Key to this is the concept of wet stock - not all underground tanks are topped off or filled up from a tanker delivery everytime (clearly if 1 tank out of 11 can take the entire contents in one go). Most tankers used to be divided into 7 chambers - 5,000 litres each (3,000 in the last one). So you'd spread the refill about and load it into different tanks in different quantities. Also allows the tanker to carry multiple grades.

I guess what I'm saying is this - the moment the error was highlighted or suspected - the Tesco / Morrison / Etc in question could shut down fuel from that source, but could easily carry on trading. The tanker which delivered it is the key - which depot, and what tank did it fill from - and where else did that go ?

All fuel companies have to maintain records of this wet stock by law, so I'm quite sure this is easy to identify. But as usual people / times / 'loading sheets' etc get in the way.

Lets see what happens.....

J.