Putting petrol in diesel car is a common and potentially very expensive mistake. The two fuels are not interchangeable, and using the wrong one can lead to significant engine damage. Here's a comprehensive guide to what happens, the warning signs, and what to do if you find yourself in this situation.

Diesel engines are designed to work with diesel fuel, which acts as a lubricant for the high-pressure fuel pump and injectors. Petrol, on the other hand, has a solvent effect, which strips away this vital lubrication. This lack of lubrication causes metal components to grind against each other, leading to friction and damage to the fuel pump and other parts of the fuel system.

If you have driven your car after misfuelling, you may notice some of the following symptoms:

Loud knocking or rattling sound from the engine:

This is a sign of improper combustion.

Loss of power and poor acceleration: The engine will not be running efficiently.

Excessive smoke from the exhaust: This is due to unburnt fuel.

The engine warning light illuminating on the dashboard.

Difficulty starting the engine or the engine cutting out.

The car may feel jerky or judder as you drive.

Do NOT start the engine. This is the most crucial piece of advice. If you realise your mistake at the petrol station, do not even turn the key in the ignition.

Inform the petrol station staff. They can help you move your car to a safe place.

Call our wrong fuel drainage service. Our service can drain the contaminated fuel from your tank and flush the system.

If you have already started and driven the car, the potential for damage is higher, but we still can help.

Even a small amount of petrol can cause damage to a modern diesel engine's high-pressure fuel system. While some older diesel engines might tolerate a very small percentage of petrol, it is not worth the risk with today's common rail diesel engines. As a general rule, any amount of petrol in a diesel tank should be considered a problem that needs immediate attention. The safest course of action is always to have the fuel drained

No matter if you are at the roadside, in a forecourt or at home, the Misfuelled Car Fixer team can come to you at any time and offer our expert fuel drain service.

To find out more, please contact us using our details below.