Passive Regeneration

The Gasoline Particulate Filter (GPF) operation and regeneration will not affect the operation of the engine when the vehicle is driven normally. Passive regeneration of the GPF occurs when the vehicle is driven normally.

The exhaust gas temperature of a gasoline engine is a lot higher than diesels.

Typically the exhaust gas temperature is

• Between 300°C and 500°C (572°F and 932°F) during urban driving
• And up to 700°C (1292°F) during continuous load situations (motorway driving).

The exhaust gas of the petrol engines contains little oxygen. The Powertrain Control Module (PCM) must increase the amount of oxygen in the exhaust gas oxygen to enable regeneration of the GPF.

The PCM when the driver removes their foot from the accelerator pedal or applies the brake pedal, the PCM stops fuel injection. The air then passes through the engines combustion chambers, without combustion increasing the oxygen in the exhaust gas. As the exhaust system is already at suitable temperature for regeneration, the additional oxygen is utilized to regenerate the GPF by oxidizing the particulate matter.

The oxidation of the particulates in the GPF passive regeneration mode

• Presents no risk of restricting the exhaust gas flow,
• And requires no intervention from the driver or the PCM.