Now we are using our cars again after periods of stand still during the confinement/lockdown period we could see an increase in fuel system faults in Petrol vehicles. As the fuel in the tank degrades and moisture enters the fuel lacquers and varnish build up in the fuel system contaminating the injectors and affecting the injector spray pattern or causing them to stick. This could result in the illumination of the engine management light and a fault code. A common fault code is P0300 Random Multiple Misfire. This code presents itself when the engine management system identifies a cylinder misfire. P0420 Catalyst Efficiency Below Threshold is also a recognised fault and can be present when the management system cannot correct the fuelling of the vehicle to maintain emissions correctly. Before replacing components, Technical Services recommend cleaning the fuel system with Wynns Petrol Extreme Cleaner or Petrol Total Action Treatment.
Cleaning the fuel system will neutralise the acids, clean and restore the injector spray patterns restoring vehicle performance and response.