Which circuit supplies fuel during idle and very light throttle openings by providing a separate fuel path?

• A. Choke circuit
• B. Idle circuit
• C. Main metering circuit
• D. Power circuit

Answer: (B)

At idle and very light throttle openings, a dedicated idle circuit provides fuel through a small, separate path that bypasses the main metering system. As air flows at idle, this circuit draws fuel from idle jets, delivering a small, steady amount of fuel to maintain a smooth idle and light-throttle response. This separation from the main metering circuit ensures the engine gets the right amount of fuel when airflow is minimal. The choke circuit is for cold-start enrichment, the main metering circuit handles mid-range fueling, and the power circuit provides a quick fuel shot during rapid throttle movement.