By the TyreAid UK team · Updated 1 November 2026
Don't start the engine
Putting the wrong fuel in is a common mistake, and it's fixable, especially if you act quickly. The less the wrong fuel moves through the engine, the less damage it can do.
If you haven't started the car
- Don't turn the ignition on. On many cars, switching the ignition on, or even unlocking or opening the door, can start the fuel pump and draw the wrong fuel into the system.
- Don't drive off. If the car is in the way, put it in neutral and push it somewhere safe.
- Call or WhatsApp us on 0330 043 6598. The tank needs draining before the car is used.
If you've already started or driven it
- Pull over safely and switch the engine off as soon as you can.
- Don't restart it.
- Call us. We'll advise you and arrange draining or recovery.
Which is worse?
Both can damage the engine and fuel system. Petrol in a diesel is usually more serious, because diesel systems rely on the fuel for lubrication. Either way, the sooner the engine is switched off, the less damage is likely.
What will it cost?
It depends on the vehicle, how much wrong fuel went in and whether the engine was started. It's usually much less if the engine was never started. We confirm the price before we come out.
How we help
We're a fully mobile service. We come to you, drain the wrong fuel, flush the system and refill with the right fuel where it's safe to work, or recover the vehicle if it needs a garage. See mobile wrong fuel drain.


