Misfuelling continues to add to motorists' costs

Article date: 31 January 2008

Latest figures from RAC Rescue show that misfuelling is on the increase with over 130 RAC members alone accidentally putting the wrong fuel in their cars on a daily basis during 2007.

RAC Rescue had nearly 50,000 call outs for misfuelling in 2007, an increase of more than 15% compared to 2006 and 385% higher than 1998. The peak time for misfuelling is between 8am and 11am on Mondays, Tuesdays, Fridays and Saturdays with 20% more instances occurring in July, August and September.

This simple error is costing motorists millions of pounds a year to put right over and above the additional pounds they are paying for fuel with prices at an all time high. Not only do they lose the value of the contaminated fuel and the cost of the repair but, to add insult to injury, they have to fill the tank again with the correct fuel.

Elvin Ravenscroft, RAC's technical development manager, says: "Drivers need to make a conscious effort to check what fuel they are about to put in their vehicle to avoid an unnecessary and potentially costly mistake.

"Once you realise that you have put the wrong fuel in your car, don't unlock the car or even put the key in the ignition (some cars now incorporate ‘easy start systems' which begin to pump fuel around the engine as soon as the door is unlocked) and under no circumstances should you start the engine. You could get away with a repair cost of around £200 to have the fuel tank drained. 

"However, if you do run the engine it can cause devastating and expensive damage. The cost could vary between £3,000 to £6,000, or more, to repair a sophisticated engine."

Hints and Tips

  • If you have more than one vehicle in the family using different fuel types, agree a colour coding for the keys (a bright green key tag for petrol cars and a yellow one for diesel vehicles)
  • Place a bright coloured reminder label inside the filler flap or even on the dashboard near the petrol gauge.

On the forecourt - diesel car

  • If you're not sure double check the markings around the filler cap to make sure it's a diesel engine - never assume
  • Check the label and colour of the pump - diesel pumps are usually yellow or black
  • Its easy to get a petrol nozzle into a diesel filler neck by mistake - if the nozzle fits very easily into the filler neck with plenty of space around it double check - WARNING petrol will damage a diesel engine
  • Ensure that the pipes have been replaced in the correct holder on the forecourt pump (ie the diesel nozzle is not in the petrol pump and vice versa)
  • Should you accidentally misfuel - do not PUT THE KEY IN THE IGNITION, turn on the ignition or start the engine - ASK RAC FOR ADVICE.

On the forecourt - petrol car

  • If you're not sure double check the markings around the filler cap to make sure it's a petrol engine - never assume
  • Check the label and colour of the pump - unleaded petrol pumps are usually green
  • Never force a nozzle into a smaller filler neck - it will be the wrong fuel
  • Should you accidentally misfuel - do not turn on the ignition or start the engine - ASK RAC FOR ADVICE.

People who drive both petrol and diesel cars reguarly or occasionally hire/borrow another vehicle should always double check the type of engine - its an easy mistake to make but could be costly.

Drivers should never attempt to drain a fuel tank themselves as this could be extremely dangerous with the risk of fire or an explosion. Petrol is also toxic and can cause serious health problems if ingested.

The problem is likely to get worse as the popularity of diesel cars continues to grow unless drivers take a few moments to ensure they put the correct fuel in their car.


RAC Press office contact:
Vicki Burn on 01603 684224 / 07800 692909

Notes to editors:

The reason why petrol contamination causes damage is:

  • Diesel fuel is ‘oily' and provides a lubrication film to the internal moving components of the diesel pump. Petrol reduces the lubrication properties allowing the very finely machined moving metal components in the pump to come into contact as the lubricating film is no longer present. This results in the metal components failing and the metal particles produced, as a result of the failure, to be pumped around the rest of the fuel delivery system
  • The whole system has to be replaced because any remaining debris will quickly re-contaminate the rest of the system should only one item be replaced
  • Petrol also changes the way in which diesel fuel ‘burns' in the engine causing an abnormal combustion process which can cause overheating of the pistons and cylinder head resulting in catastrophic engine failure.

About RAC
With around seven million members, RAC is one of the UK's most progressive motoring organisations, providing services for both private and business motorists.  Whether it's roadside assistance, windscreen repair and replacement, learning to drive, vehicle inspections and checks, legal and financial services or up-to-the-minute traffic and travel information - RAC is able to meet motorists' needs. RAC incorporates BSM, RAC Auto Windscreens, RAC Direct Insurance and HPI.

RAC is committed to providing the very highest levels of service to its members and has been ranked first for customer service by J D Power and Associates' UK Roadside Assistance Study for the past two years.

Aviva bought RAC in May 2005. The acquisition brings together RAC's powerful brand and customer base with the expertise and leading position in motor insurance of Norwich Union Insurance (part of Aviva). Norwich Union is the UK's largest insurer, insuring one in seven motor vehicles and with a market share of around 15%.

RAC's news releases and a selection of images are available from the internet press centre at http://www.racnews.co.uk.

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