Its function is to quickly pull the choke plate open once the engine starts. The choke partially restricts airflow to enrich the fuel/air mixture during cold starts, helping the engine to fire and run until it warms up. The manual choke mechanism (the choke lever) initially closes the choke. Once the engine starts, the choke pull-off solenoid is energized, overcoming the spring tension and rapidly pulling the choke plate open a small amount, preventing excessively rich running as the engine warms. The choke then continues to open gradually (either automatically via a thermostatic choke, or manually by the driver) as the engine warms up.
