Picture this: you’ve just finished filling up at a petrol station in the UK, put the nozzle back, and suddenly realise — you’ve put the wrong fuel in your car. Your first instinct might be to quickly start the engine and “just drive a little” to see if it runs. Unfortunately, that’s the worst thing you can do.

Starting your car after misfuelling can cause the contaminated fuel to circulate through your engine, fuel pump, and injectors, leading to costly damage. For diesel engines, petrol acts as a solvent, stripping away the lubrication the system relies on, while for petrol engines, diesel can clog components and prevent combustion. Either way, you’re risking a much bigger repair bill than necessary.

In this blog, we’ll break down exactly what happens when the wrong fuel reaches your engine, why acting quickly is essential, and what steps you should take instead. We’ll also explain how professionals like Wrong Fuel Doctors can remove the contaminated fuel safely without causing further harm to your vehicle.

With our nationwide 24/7 service across the UK, we can get to your location fast, drain your tank on-site, and ensure your car is back to running smoothly — without the nightmare of engine replacement costs. So before you turn that key, read on and learn why waiting for expert help is the smartest move you can make after misfuelling.