If you haven’t started the engine
- Don’t turn the ignition on. On many cars, even switching on the ignition starts the fuel pump.
- Tell the forecourt staff. They’ll help you push the car out of the way.
- Put it in neutral and push it to a safe spot, with help.
- Arrange a fuel drain, either a mobile fuel-drain service or recovery to a garage.
If you’ve already driven off
Petrol in a diesel usually causes knocking, smoke, loss of power and stalling. Diesel in a petrol car causes misfiring and smoke. As soon as you notice, pull over safely, switch off and don’t restart it. The longer it runs, the more damage to the fuel pump and injectors.
Drain on site or recover?
A mobile fuel-drain service can often empty the tank at the forecourt. If the engine has run on the wrong fuel, or the garage needs to flush the system, the car should go to a garage. We recover it there. See breakdown recovery.
Tell your insurer: some policies cover misfuelling, but many don’t.
FAQ
Straight answers
Can I drive with a little bit of wrong fuel?
It’s not worth the risk. Even a small amount can cause damage, especially petrol in a modern diesel. Get advice before starting the engine.
Is petrol in a diesel worse than diesel in a petrol car?
Usually, yes. Petrol in a modern diesel can damage the high-pressure fuel pump and injectors. Diesel in a petrol car tends to cause misfiring and smoke, and is often cheaper to fix. Either way, don’t start the engine.
Will my insurance cover wrong fuel?
Some policies cover misfuelling, many don’t. Check your policy before booking the work.