Source of contamination in unleaded petrol is discovered
2 March 2007

Petrol believed to be at the root of problems suffered by thousands of motorists across the south east of England has been found to contain high levels of silicon.

Fuel from petrol stations operated by supermarket chains Tesco and Morrisons was at the heart of the problem, though other retailers were also affected.

All of the affected petrol stations source their fuel from the same depot in Essex, run by Dutch company Royal Vopak.

Tesco's own tests revealed "significant silicon contamination" in the fuel.

As a result, Tesco is to remove all unleaded petrol from 150 of its petrol stations in the south east, though it will restock and continue to supply petrol.

Morrisons earlier stopped selling fuel at 41 of its petrol stations supplied by Vopak.

Silicon is used as an anti-foaming agent in diesel fuel, but should not be in petrol. Cars that have filled up with the contaminated fuel have suffered from pinking and stalling, and many have had to be taken to garages on recovery trucks.

Garages have said that the cars have suffered problems with their lambda sensors (pictured), which measure the exhaust gas mixture and control fuelling.

Add your comment

Log in or register to post comments

Find an Autocar car review

Driven this week

  • Lexus LC500
    Car review
    20 October 2017
    Futuristic Lexus LC coupé mixes the latest technology with an old-school atmospheric V8
  • Maserati Levante S GranSport
    First Drive
    20 October 2017
    Get ready to trade in your diesels: Maserati’s luxury SUV finally gets the engine it’s always needed
  • Jaguar XF Sportbrake TDV6
    First Drive
    19 October 2017
    The handsome Jaguar XF Sportbrake exhibits all the hallmarks that makes the saloon great, and with the silky smooth diesel V6 makes it a compelling choice
  • Volkswagen T-Roc TDI
    First Drive
    19 October 2017
    Volkswagen's new compact crossover has the looks, the engineering and the build quality to be a resounding success, but not with this diesel engine
  • BMW M550i
    First Drive
    19 October 2017
    The all-paw M550i is a fast, effortless mile-muncher, but there's a reason why it won't be sold in the UK