What happens if the incorrect fuel has been used?

Discover the critical consequences of using incorrect fuel, such as petrol in a diesel engine or diesel in a petrol engine. Learn why starting the engine is strictly advised against and how to mitigate costly fuel system damage.

Should you inadvertently use the wrong fuel in your Ford vehicle, do not attempt to start the engine. Starting the vehicle can cause extensive and costly damage to the fuel system, which may not be covered under your Ford Express New Vehicle Warranty. Immediate inspection by a qualified technician is crucial.

Petrol in a Diesel Car: Introducing petrol into a diesel vehicle acts as a solvent, drastically reducing the lubricating properties of diesel. This critically compromises the fuel pump and other fuel system components due to increased metal-on-metal friction. Activating the ignition circulates this damaging mixture, potentially leading to severe, expensive repairs or complete fuel system replacement.

Diesel in a Petrol Car: While generally less severe, putting diesel into a petrol vehicle can still cause significant issues. If the engine is started, diesel can coat spark plugs and the fuel system, resulting in misfiring, excessive smoke, or complete engine failure. The vehicle may cut out or fail to start at all.

For comprehensive details, please consult your vehicle's owner's manual.