From their website:

01/03/2007 - Tesco statement on customer petrol concerns

We are continuing to conduct a range of tests using independent
laboratories to establish what might be causing the mechanical problems
experienced by some customers in the South East of England. So far we
have not found any reason for these problems.

However, following advice from industry experts we have now started
testing for silicon and other possible contaminants. We are also
checking the levels at which any contaminant would start to cause engine
problems. We hope to have results back soon and will of course share
these with the other supermarkets and petrol retailers who are affected.

In the meantime we have set up a customer hotline for any Tesco
customers who have experienced a problem. This Freephone number is 0800
0286428.

We appreciate the inconvenience this is causing some customers and can
assure them that if a problem with our fuel is confirmed we will do the
right thing and act quickly to put it right.

On Sat, 03 Mar 2007 17:38:40 +0000, Tony Brett <tony (AT) tonybrett (DOT) org.uk>
wrote:

Morrisons and Asda still are not saying anything -
<URL:http://www.morrisons.co.uk/192.asp>,
<URL:http://www.asda-press.co.uk/>

Harvest Energy who appear to be the source of the problem -

"Press release 10am Saturday 3 March 200710am Saturday 3 March 2007

STATEMENT BY HARVEST ENERGY ON
SOUTH EAST OF ENGLAND FUEL SUPPLY ISSUES

Harvest Energy has this morning announced that it has completed its
initial investigation of possible fuel contamination of the product
stored at the oil terminal owned by Vopak at West Thurrock, Essex. The
company, which has been trading in the UK since 1995, shares the
terminal’s facilities with Greenergy, another independent blender and
wholesaler of fuels.

The testing has identified unusually high levels of silicon in four
petrol storage tanks at the terminal. Fuel blended from these tanks
has been supplied to various petrol retailers who take fuel from the
West Thurrock terminal.

Harvest Energy’s testing confirms that its petrol reaches the European
and British specification BS EN 228 for unleaded fuel. However, the
specification does not include a test for silicon, as it is not an
element that would normally be expected to be present within finished
grade petrol or blend components, and for this reason its presence was
not detected prior to sale. We will now be testing for silicon as a
matter of course. In addition Harvest Energy will propose to the
relevant European and British Standards organisations, via its trade
body the Association of UK Oil Independents (AUKOI), the inclusion of
a silicon test within the BS EN 228 standard for unleaded petrol.

The company is also keen to work with the Society of Motor
Manufacturers and Traders (SMMT) to help identify the presence of
other elements that may not currently be included in the BS EN 228
specification and which the SMMT believes may have an adverse impact
on vehicle performance.

Harvest Energy has now isolated the higher silicon fuel and can
guarantee that no further supplies of high silicon unleaded petrol
will be distributed from the West Thurrock terminal. All petrol at the
terminal currently available for distribution has minimal (less than
one part per million) silicon levels in line with usual industry
norms.

Harvest Energy is working with its customers who retail petrol to
British motorists to allow them to ensure that all future product sold
is of the usual expected standard. As part of this process, the
company has appointed an independent inspection company to test fuel
stocks at over 100 petrol stations across the South East over the
weekend.

Harvest Energy Managing Director Franco Bussandri said “We are very
sympathetic to the plight of motorists who have been affected by this
problem with unleaded petrol. We are working as closely as we can with
our customers the retailers, to address such motorists concerns. We
would ask motorists who feel they may have been affected to contact
their fuel retailer for advice.”

- Ends - "

<URL:http://www.harvestenergy.co.uk/news_story.php?articleID=20>

"Daytona" <me (AT) privacy (DOT) net> wrote

Well if you must all drive these cars with newfangled computery gadgets. It
won't affect real cars with carburettors.

Seriously though, does anyone know if it is possible to wash off silicon
from the oxygen sensor without damaging it?

Brian <blecnospam (AT) tesco (DOT) net> wrote:
<snip>
No.
Some people have reported success heating it with a blowtorch in air
though.
The oxygen sensor is generally not that expensive fortunately.

On Sun, 04 Mar 2007 11:36:14 GMT, "Brian" <blecnospam (AT) tesco (DOT) net>
wrote:

I don't know if it's as simple as that.

I have an '89 Golf and have driven 140 miles on Morrisons (Chippenham)
petrol. I've no idea if it is the silicone enriched petrol.

Good question.

Daytona

"Daytona" <me (AT) privacy (DOT) net> wrote

I've heard of people successfully cleaning oxygen sensors with a blowlamp
before.

On 2007-03-04, Daytona <me (AT) privacy (DOT) net> wrote:
Does an '89 Golf have an oxygen sensor? It's from about the time when
some but not all cars had catalysts.

I phoned Tesco's "helpline" and they couldn't tell me any more than that
the station I had filled up was implicated, but they have a lot of
deliveries, they top up tanks that aren't quite empty, not all tankers
come from the dodgy depot, etc.

At least one other person who filled up there I know started having
problems within the first few miles of driving away, after filling an
already half-full car. I had filled up from empty and already driven
about 30 or 40 miles with no trouble before I heard about the problem on
the news. I considered draining out the remaining petrol, but it's not
easy to dispose of the stuff, and there's always the risk of ending up
with a Darwin award if I start messing around with petrol.

In the end I thought I'd just gamble on it being OK, because the cost of
a sensor is not much more than the cost of the full tank of petrol
anyway and in any case I'd claim it from Tesco. I've now done another 80
miles and it's still running fine. Maybe the silicone deposits are
slowly building up, or maybe I was lucky and didn't get the bad fuel, or
maybe my particular brand of oxygen sensor isn't so sensitive. When it
gets to half-full, perhaps I'll top it up with some nice Esso or Shell
to dilute the silicone if it's in there.

I think it likely a lot of people's problems started very soon after
filling up or it wouldn't have been so obvious the fuel was to blame, so
if you've done 140 miles you might be all right.

On Sun, 04 Mar 2007 12:36:32 -0600, Ben C <spamspam (AT) spam (DOT) eggs> wrote:

It doesn't have a catalyst, but I can see no reference to an oxygen
sensor or Lambda in the Hayes manual, but then again there's no
reference to them on catalyst models either :-)

I'm continuing to drive it thanks to the info. I've gleaned from this
newsgroup. No thanks to Trading Standards, the media and the companies
involved.

Daytona

On 2007-03-05, Daytona <me (AT) privacy (DOT) net> wrote:
If you have a catalyst you'd expect to have a sensor, since getting the
mixture wrong might damage the cat, so you need the fine control that
you get with a sensor. Some pre-cat cars may have had sensors anyway
just for accurate mixture control and good economy etc.

My local garage said they've just been changing people's sensors without
draining the fuel. I can't see the logic behind that unless you didn't
know the fuel was the problem or you aren't playing with a full deck.

I had an 1987 fiesta with "issues" so .go fo it

stptop worryimg obout stuff,just because youte0fulleec in thevlastv30 yeras
and just o or it bcause you had uihgoiup087t08gt8p778g8gti7