Diesel in a Petrol Car

Putting diesel in a petrol car is a common mistake and in 99.9% of situations is able to be fixed.

The result of putting diesel in a petrol car can be due to a mix up from the mislabeling of jerry cans that have diesel in them or being tired and distracted at a fuel station.

What to do ?

DO NOT START YOUR ENGINE or put your key into the ignition as this can prime the electric pump in the tank and circulate the wrong fuel. It is essential to carry out a full fuel drain. Once the contaminated fuel has been removed and the tank filled with the correct diesel there should be no damage to the engine.

Already driven the car before realising?

If you have already started your vehicle, STOP driving as soon as it is safe to do so.

With this situation, it is recommended to take every precaution to remove all of the wrong fuel. A full tank drain, and complete fuel system flush is essential to stop or minimise any potential damage from to your vehicle’s fuel system.

If the vehicle has broken down as the result of putting diesel in a petrol car, once the system has been completely flushed through with the correct fuel and the tank has been filled with petrol, the spark plugs will need to be cleaned or replaced to remove any carbon deposits.
In many cases petrol vehicles will log cylinder misfire faults on the engine management system. Our mechanics are provided with the latest scan tools and software to clear and review any fault codes and to check your engine is running as normal following our repairs.

Reduce the risk

Always double check the fuel grade indicator on the pump before filling.

Our biggest word of advice is to always double check the fuel grade indicator on the pump before filling up.

Below are some indicators to be wary of that can increase the risk of mis-fueling:

  • You use an unfamiliar filling station – don’t assume hose colours are the same as your ‘local’ site
  • You switch between brands using different hose/nozzle colours
  • You swap cars (using different fuel) at home or work – it’s easy to ‘forget’ which car you’re filling
  • You hire a car using different fuel to your normal car
  • You buy a new car using different fuel to your old car
  • You continue a conversation with passengers while filling
  • You are in a hurry/running late