Methods and systems for reducing emissions of a hybrid vehicle

A system, comprising:

• an engine;
• an integrated starter generator (BISG) coupled to the engine;
• a starter motor coupled to the engine;
• a battery configured to power each of the BISG and the starter motor;
• and
• a controller with computer-readable instructions stored on non-transitory memory that when executed cause the controller to:
• determine an engine soak time;
• in response to the engine soak time being greater than a threshold soak time;
• determine a state of charge (SOC) of the battery and compare the battery SOC to a threshold SOC;
• activate an electric exhaust gas heater (eEGH) in response to the battery SOC being greater than the threshold SOC;
• and
• start the engine using the starter motor in response to an ambient temperature being less than a threshold ambient temperature.

A method, comprising:

• determining a battery state of charge (SOC) and comparing the battery SOC to a threshold SOC;
• activating an electric exhaust gas heater (eEGH) in response to the battery SOC being greater than the threshold SOC;
• and
• starting an engine using a starter generator in response to an ambient temperature being greater than or equal to a threshold ambient temperature during a cold-start of the engine.