RE: Supermarket fuel: is it good enough?

RE: Supermarket fuel: is it good enough?

Author
Discussion

Al 450

1,390 posts

220 months

Thursday 1st March 2007
quotequote all
trendytramp said:
Eddy5 said:
I'm an auto engineer working for a supplier of EMS (Engine Management Systems) to manufacturers, and can see no way that if ethanol was added to the petrol it would damage the oxygen sensor. They are usually messed up by oil contaminates or lead contaminates in the fuel. My guess as to the reason they are changing the sensor is that the EMS is falsely diagnosing a fault with the sensor, as it was never calibrated to see an ethanol fuel.
My first thing to do would be to drain the fuel tank, fill up with a good source of fuel and then clear the fault codes and see what happens. I'd expect everything to be fine.


I agree - as someone else in the industry I'd guess the sensor is seeing an AFR variation outside of it's normal operating range which is flagging a fault and going into limp home mode.
As you say, draining the tank and clearing fault codes, not changing the sensor is probably the solution (aand cheapest).


Depending on the contaminant though there could well be further damage to the engine that is not visible for years. I wouldn't blame the bio-ethanol as this hasn't been a problem before. There is clearly something amiss at the refinery. I'm not a powertrain guy but i'd think a problem affecting the octane rating or water contamination could be pretty serious?

The OBD system of a vehicle is there to adapt fuelling and ignition to suit a variety of factors, to optimise efficiency and prevent damage. The oxygen sensor is the symptom, the fuel the root cause but what are the long term effects ? I don't think anyone can truly know.

Of course cars without smarty pants OBD systems like mine will just suffer the effects without displaying a symptom which is even worse!

bunglist

545 posts

229 months

Thursday 1st March 2007
quotequote all
I have always used optimax since it was released and now use the V-Power which is the replacement, I have never had any bad fuel, well not that I know of.

But I will not put anything else in my car V-Power only.

bumpkin

158 posts

254 months

Thursday 1st March 2007
quotequote all
since i have suffered from this some thoughts would be useful: st170 04 model 78k on the clock

i filled up monday morning with 45 or so litres of tesco regular unleaded fuel, tank was almost empty. drove approx 70 miles and on comes the engine light. there was a short time (seconds) when i could feel the engine not running properly, then it felt ok, mind i had slowed down. car has just been serviced and as you'll note from my mileage that fuel doesn't stay in the tank long.

i have also heard cats have been damaged not just oxygen sensors.

the only theory i can think of is the fuel has a very high level of ethanol say 85% and the resultant leaning off of mixture has done the damage.

my first thought was a sensor had given up the ghost due to the mileage. cars off to the garage friday for diagnosis.

trev r

95 posts

258 months

Thursday 1st March 2007
quotequote all
I read the current "we do not know what caused this yet" fuel contamination news stories as "we f***d up, and we're trying to think how to get out of it before we announce what we did wrong/blame someone else"

Does anyone else feel that the fuel suppliers and supermarkets are at this very moment creating the perfect amount of PR-spin for a press release that results in motorists being stuffed and their cosy big bucks busiess getting away without blame?

Meanwhile main dealers are making the most of it and being creative (as usual) with the costs of fixing the problems....as mentioned above, drain fuel/refill with good stuff, reset ECU/EMS and most will be fixed. No need for new parts and hours of investigation!

over_the_hill

3,185 posts

245 months

Thursday 1st March 2007
quotequote all
ringram said:
If so then it sounds like the garage was more concened about making money out of the customer than working out what the problem acutally was.

More likely that they are not capable of working it out. Car comes in, plug in diagnostic tool. Result - faulty lambda sensor. Look up part number and instructions to fit.
Charge customer for part, fitting and usual main dealer mark up.

Ruaraidh_Gamma

69 posts

218 months

Thursday 1st March 2007
quotequote all
There will be a backlash against the current media frenzy when the truth gets out: 1000s of O2 sensors o not fail at once. The fuel is the problem and the Sensor goes (correctly) out of range triggering the fault.

The Garages are shortly going to be found out for replacing expensive sensors which are perfectly fine. Quick drain and clear the codes is all that's required. Anyway, 02 sensors can be bought cheaply enough (Local factors has them for 30quid) and only Bosch, Denso and NTK (NGK) make them anyway.

The fuel is the problem, the sensor is a symptom, the fuel company is in denial, the garages are making a killing and the BBC is in disinformation "Vox Pops" overdrive. Situation normal then.

Al 450

1,390 posts

220 months

Thursday 1st March 2007
quotequote all
Just checked around at work and apparently if the fuel has too high an ethanol content (octane I assume) then burnt valves and a scrap cylinder head could be likely. Feel sorry for anyone affected

chrisbr68

4,121 posts

247 months

Thursday 1st March 2007
quotequote all
I saw a woman on the news this morning. Aparently her garage told her that she needed a new ECU at the cost of a grand.

DucatiGary

7,765 posts

224 months

Thursday 1st March 2007
quotequote all
Tesco said:
it is unfortunately quite common for mistaken rumours to arise as to the provenance of car maintenance issues


so Tesco are saying these people, from all over the country, they all have the same problems due to not looking after your car, all at the same time, all after filling up with supermarket fuel.

scum, its one thing to try and dodge responsibility whilst looking into the matter but its another to try and make out its your own fault becuase you obviously dont look after your car propperly.

then again they might have a point, if you looked after your car you wouldnt fill up at a supermarket!

S2 Giles

2,870 posts

274 months

Thursday 1st March 2007
quotequote all
Ethanol is not the same as octane - high octane fuels also have a high level of cleaners in them that are far better for the cylinder head

mk1fan

10,507 posts

224 months

Thursday 1st March 2007
quotequote all
Mine has run fine on 99 super from Tescos ever since the fuel was released. I think that a single batch of fuel may have been contaminated.

Tinohead

639 posts

208 months

Thursday 1st March 2007
quotequote all
GETSIS said:
Ray Holloway, director of the Petrol Retailers' Association, said even motorists who have not been affected might want to consider dumping the fuel in their tanks.

He said: "Motorists who have not been affected could save themselves a bill by changing the petrol in their tanks. That would be my recommendation."


Is that so Ray, I wonder why you would want hundreds, maybe thousands of motorists to dump tank loads of petrol and then go fill up again? Could it be anything to do with the fact that you are the director of the association that represents the people seeling petrol!??!?! idea nono

dern

14,055 posts

278 months

Thursday 1st March 2007
quotequote all
Ruaraidh_Gamma said:
There will be a backlash against the current media frenzy when the truth gets out: 1000s of O2 sensors o not fail at once. The fuel is the problem and the Sensor goes (correctly) out of range triggering the fault.

The Garages are shortly going to be found out for replacing expensive sensors which are perfectly fine. Quick drain and clear the codes is all that's required. Anyway, 02 sensors can be bought cheaply enough (Local factors has them for 30quid) and only Bosch, Denso and NTK (NGK) make them anyway.

The fuel is the problem, the sensor is a symptom, the fuel company is in denial, the garages are making a killing and the BBC is in disinformation "Vox Pops" overdrive. Situation normal then.

Completely agree. I diluted my fuel with new fuel, reset the ecu and cleaned the maf and icv while I was in there and it seems to get rid of all of the symptoms that gradually appeared over the track day I'd got after sticking a 1/3 of a tank of Tesco's 99 in before I started. Quite glad the fuel in the tank wasn't any less dilute.

Regardless of whether or not people are jumping on the bandwagon it would appear than there actually is a problem. I don't know if my problem was caused by the fuel from tesco but it did come completely out of the blue. I won't be taking my case any further as it didn't cost me anything to fix and have no more evidence that it was the fuel's fault other than the coincidental poor running.

I'll certainly use tesco's fuel again once they sorted the problem out and genuinely don't believe supermarket fuel is particularly inferior to any other kind of fuel. I certainly don't believe all the marketing crap from shell about their optimax/v-power fuel being vastly superior. As for companies like shell always offering great quality fuel... anyone remember shell fuel's effect on certain jag and bmw's nikasil'd engines a few years back?

Edited by dern on Thursday 1st March 12:47

TheM5man

2 posts

204 months

Thursday 1st March 2007
quotequote all
My wife's car - a 206CC - has just died and the garage confirm the oxygen sensors have gone and indeed it looks like the petrol. We bought it from Tescos Burgess Hil, W Sussex - so strongly recommend no-one buys petrol from supermarkest but stick to main brands. Car needs new sensors (now in short supply) and tank drained. They are keeping samples of the petrol as evidence. Someone somewhere is going to pay and it ain't going to be me!!

So careful out there guys and gals.

sawman

4,915 posts

229 months

Thursday 1st March 2007
quotequote all
Well for once theres no queue to buy pterol at my local tescos. Mt wife just came back and asked is there something wrong with tesco petrol? the petrol station was deserted - so she filled up!

Havent noticed any probs and we always use tesco 99

jezza l

385 posts

228 months

Thursday 1st March 2007
quotequote all
My Clio trophy was affected by a fueling problem which started early Jan. The car has NEVER been filled up with a supermarket fuel and has only been filled up on BP ultimate and 99% of the time it's filled up with V-power. I experienced exactly what the drivers affected by this contamination experienced. Sudden power loss, regardless of gear, speed or rpm. Renault originally replaced the air inlet solenoid, but the issue came back i then had the oxygen sensor replaced. I've have probably thought it has nothing to do with contaminated fuel however i've heard from people that early reports thought V-power was affected by this. So anyway i'm just adding my experience.

Munter

31,319 posts

240 months

Thursday 1st March 2007
quotequote all
TheM5man said:
My wife's car - a 206CC - has just died and the garage confirm the oxygen sensors have gone and indeed it looks like the petrol. We bought it from Tescos Burgess Hil, W Sussex - so strongly recommend no-one buys petrol from supermarkest but stick to main brands. Car needs new sensors (now in short supply) and tank drained. They are keeping samples of the petrol as evidence. Someone somewhere is going to pay and it ain't going to be me!!

So careful out there guys and gals.


Based on this i'd say ask them to clean up the sensors, refill with good fuel and see if it runs ok.... No way i'd pay out to have a sensor changed without trying a clean batch of fuel first.

Philbes

4,337 posts

233 months

Thursday 1st March 2007
quotequote all
£90 or £30 for a lamda sensor! I wish. When the sensor failed on my 2002 Honda Accord 2.0 litre a year ago two £80 3rd party 'compatible' replacements proved not to be compatible. The genuine Honda supplied part worked immediately but cost £253+VAT. Thank God that was the only replacement part I had to buy in nearly 3½ years and 42K miles.

baSkey

14,291 posts

225 months

Thursday 1st March 2007
quotequote all
what i don't get is..

i thought it was only 99ron from green energy... i though the normal 95 was 'generic nearest refinery to you'....???


Edited by baSkey on Thursday 1st March 13:06

Mr Whippy

28,944 posts

240 months

Thursday 1st March 2007
quotequote all
Foil hats on.

Government spikes cheaper supermarket fuels to reduce usage and create demand for higher cost higher VAT laden "brand" fuels hehe


Supermarket fuel is great, clearly just a mistake somewhere along the line that any supplier could have made.

Quite amusing seeing all the garages just saying "computer says lambda sensor, £100"

Dave