METHOD AND SYSTEMS FOR AIRFLOW CONTROL

Various methods and systems are provided for controlling emissions. In one example, a controller is configured to respond to one or more of intake manifold air temperature (MAT), intake air flow rate, or a sensed or estimated intake oxygen fraction by changing an exhaust gas recirculation (EGR) amount to maintain particulate matter (PM) and NOx within a range, and then further adjusting the EGR amount based on NOx sensor feedback.