If you have put petrol in a diesel car or diesel in a petrol car, do not start the engine and do not turn the key to the ignition position. Starting the car pumps the wrong fuel through the system and turns a simple drain into an expensive repair.
What to do straight away
- Do not start the engine or switch on the ignition.
- If you are still at the pump, tell the station staff and, with help, push the car to a safe place off the forecourt.
- Keep the key out of the ignition. Even switching to accessory mode can prime the fuel system.
- Note how much of the wrong fuel went in and whether the engine was started at all.
- Call for recovery so the tank can be drained, or the car taken to a garage.
Petrol in a diesel, and diesel in a petrol
Petrol in a diesel is the more damaging mix, because petrol strips the lubrication the diesel fuel system relies on. Diesel in a petrol car is less common, as the nozzle is larger, but it still needs draining before the car is driven. In both cases, not starting the engine is the single most important thing.