tesco diesel in d5

[cooltide]

Thought I would share my recent experience with tesco diesel in our s60 d5 56 plate.
3 weeks ago car serviced. We had to travel to the west Midlands and back to Durham so my wife filled up at tesco bishop Auckland with a whopping 12p off a litre from the shopping. I had to make a 70 mile journey so reset the CPU to see if the mpg had improved post service. To my horror I averaged 34.6 on a journey that should see 40+.
Checked garage had actually changed air filter. Checked injector pipes hoses etc.
2 days later we set off for w.MIDs.
Mpg peaked at 37.8 around manc and levelled out for the rest of the motorway leg. Dropped to 37.1 at wombourne.
Topped up the remaining third of a tank with 6 gallon of shell diesel. Mpg started climbing again immediately when it had been falling on the single track roads. 200 miles home and the average had risen to 40.1. I would normally expect to see an average of 44-45 altogether.
I realise that this is hardly scientific but the gauges have proved reliable and consistent. Thought I had a problem till I topped up with shell.
Should have smelled a rat with 12p off.

[Mr-V70]

Interesting you should say that, I noticed something very similar - I didn't check the MPG readout, but I used 3/4 of a tank on a journey that normally uses 1/2 tank after filling up at Tesco.

Didnt think much of it until reading your post....

S

[Mark S60D5]

Very interesting as I noticed mine was smoking last week after I had bought fuel in tesco, it doesnt normally smoke at all!

[martinrpeachey]

Don't know about their Derv but their petrol is usually crap. The 95 ron stuff is like all the other cheap 95 but the "momentum" (probably because you'll be relying on the car's momentum to keep it going) is pants. It's octane is boosted using bioethanol (giving Tesco a kickback from the government for using a part-biological fuel) an doesn't contain the same energy as Shell V-Power.
In my car (lightly modified and mapped to run 97ron or above), I don't get as much power as the Shell stuff but my MPG drops by about 4-5.

[Rossey]

All fuels now will have to contain a certain percentage of renewable fuel.

If you have a diesel you need a cetane booster.

I run my 2.5tdi on biodiesel and add acetone which helps a lot and currently returning 42.5 mainly town driving.

[CJL]

Wouldn't even put Tesco fuel in my mower.

[skyship007]

Originally Posted by Rossey

All fuels now will have to contain a certain percentage of renewable fuel.

If you have a diesel you need a cetane booster.

I run my 2.5tdi on biodiesel and add acetone which helps a lot and currently returning 42.5 mainly town driving.

In general terms cetane boosters don't work too well AND Acetone is an absolute no go additive for any diesel or petrol fuel system. It can degrade the fuel tank sender unit and the seals inside the high pressure pump if used long term.

Bio diesel is a very good natural solvent, so the fuel system and injectors will stay clean. Alas it has a much higher flashpoint than normal diesel so is bad news if it contaminates the engine oil, as it does not evapourate off much when warm.
Pure Bio from a farm might clean well AND is an excellent lubricity additive for normal diesel, BUT that does not mean it does not get dirty.
It also has a lower gell point in winter, so most users either switch to winter diesel, or if they are far enough South just mix it 50/50 with a good winter diesel.
The other winter option is to use an anti gell (It stops wax forming in the fuel filter) fuel additive.

[scutle]

Originally Posted by cooltide

Thought I would share my recent experience with tesco diesel in our s60 d5 56 plate.
3 weeks ago car serviced. We had to travel to the west Midlands and back to Durham so my wife filled up at tesco bishop Auckland with a whopping 12p off a litre from the shopping. I had to make a 70 mile journey so reset the CPU to see if the mpg had improved post service. To my horror I averaged 34.6 on a journey that should see 40+.
Checked garage had actually changed air filter. Checked injector pipes hoses etc.
2 days later we set off for w.MIDs.
Mpg peaked at 37.8 around manc and levelled out for the rest of the motorway leg. Dropped to 37.1 at wombourne.
Topped up the remaining third of a tank with 6 gallon of shell diesel. Mpg started climbing again immediately when it had been falling on the single track roads. 200 miles home and the average had risen to 40.1. I would normally expect to see an average of 44-45 altogether.
I realise that this is hardly scientific but the gauges have proved reliable and consistent. Thought I had a problem till I topped up with shell.
Should have smelled a rat with 12p off.

I tend to keep away from supermarket fuel cause of poor MPG & engine problems

[x70jwo]

The quality of Shell, Esso, BP, Total, Texaco, etc. ex refinery, in the majority of cases is much better than supermarket fuel. The latter usually is blended from cheap hydrocarbon component fractions to just meet the legal requirements (although at times, supermarket's diesel will be from a surplus refinery batch). I have compared premium with regular diesel in my XC70 D5 AWD man Polestar and found that the extra cost for premium is offset (break even) by better economy. So I'm using the premium stuff as it produces less soot keeping the particulates filter clean. Polestar in combination with normal driving improves fuel economy by 8%

[green van man]

I found the polestar made very little difference to economy but increased the size of the smile on my face

Paul.