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Silicon found in petrol samples Silicon found in petrol samples
(30 minutes later)
Trading standards officers have confirmed silicon has been found in petrol taken from the tank of a car affected by allegedly faulty fuel. Tests on petrol taken from the tank of a car affected by allegedly faulty fuel have detected the presence of silicon, trading standards officers have said.
Faulty unleaded petrol has been blamed for causing thousands of cars to break down, mainly in south or east England.Faulty unleaded petrol has been blamed for causing thousands of cars to break down, mainly in south or east England.
Cambridgeshire County Council's trading standards department had the fuel sample tested at a London forensic science laboratory. Silicon products are used in diesel as anti-foaming agents, but can cause "serious problems" in petrol engines, a trading standards official said.
Tests carried out for Tesco and Morrisons have found no fault so far.Tests carried out for Tesco and Morrisons have found no fault so far.
Many drivers said they had filled up at the two supermarkets before their cars started to show problems such as juddering and misfiring.Many drivers said they had filled up at the two supermarkets before their cars started to show problems such as juddering and misfiring.
Silicon can build up as a deposit on sensors causing them to malfunction Ian Hillier,Trading Standards Institute
Cambridgeshire County Council's trading standards department had the fuel sample tested at a London forensic science laboratory.
Ian Hillier of the Trading Standards Institute said in a statement that silicon could particularly cause problems in modern cars with computerised fuel management systems.
"Silicon can build up as a deposit on sensors causing them to malfunction," he said.
The findings were preliminary and further tests were being carried out, he said.
Insulator
A spokesman for Cambridgeshire Trading Standards said detecting silicon in the fuel could indicate the presence of silicone, the chemical compound containing the element.A spokesman for Cambridgeshire Trading Standards said detecting silicon in the fuel could indicate the presence of silicone, the chemical compound containing the element.
Silicone is used in industry as an insulator and for lubrication.Silicone is used in industry as an insulator and for lubrication.
The spokesman said the test had yielded only an initial result, not the final conclusion. The spokesman said oxygen sensors from faulty cars were being sent to a laboratory for analysis to discover what had made them stop working.
"It points us in a direction. The tests found the element silicon, which suggests the presence of silicone."
He said they were also sending off oxygen sensors from faulty cars to a laboratory for analysis to discover what made them stop working.
The petrol has been traced to a storage depot in Essex. The fuel industry is testing its own supplies.The petrol has been traced to a storage depot in Essex. The fuel industry is testing its own supplies.
It is thought silicone may have found its way into a batch of petrol in transit by ship into the UK or in storage containers.It is thought silicone may have found its way into a batch of petrol in transit by ship into the UK or in storage containers.
Automotive expert Professor Malcolm Fox, from the University of Leeds, said low levels of silicone could affect a car's performance.Automotive expert Professor Malcolm Fox, from the University of Leeds, said low levels of silicone could affect a car's performance.
"When it burns, it will form silicon dioxide and will deposit a very thin sheet on the sensor - the sensor is in the exhaust - and that probably gives a false signal to the engine computer.""When it burns, it will form silicon dioxide and will deposit a very thin sheet on the sensor - the sensor is in the exhaust - and that probably gives a false signal to the engine computer."