Ignition Stability Improvement and Emission Reduction via Multiple Ignition Sites Strategy Under Cold Start and Transient Conditions

Abstract Downsizing, turbocharging, and lean burn strategies offer improved fuel efficiency and engine-out emissions to that of conventional spark ignition engines. However, maintaining engine stability becomes difficult, especially at low load and low speed operation such as cold start conditions. Under cold start operation, the spark timing is retarded to rush catalyst warm-up temperature followed by advancing the spark …