System and method for adjusting engine airflow

摘要

Methods and systems for operating an engine during conditions where ambient humidity changes over time are presented. In one non-limiting example, an engine airflow is adjusted to increase engine airflow during high humidity conditions such that an engine may provide equivalent torque output during the high humidity conditions as compared to when the engine is operated during low humidity conditions.

主权项

1. An engine operating method, comprising:
adjusting spark timing advance/retard responsive to ambient humidity to reduce knock; adjusting engine airflow responsive to desired engine torque, the engine airflow adjusted responsive to a partial pressure of oxygen in air; and adjusting an estimated engine torque responsive to the partial pressure of oxygen in air in addition to the adjusted spark timing retard/advance, the partial pressure of oxygen in air based on ambient humidity.