Throttle Body

In response to depressing throttle pedal, the throttle body opens and closes its valve to regulate air volume to the combustion chamber. Vacuum is applied to various ports for ignition timing, EGR valve and canister purge.

More than half of the air necessary for idling is supplied to the intake manifold via the idle by-pass passage. Turning idle adjust screw on the idle by-pass can change airflow to adjust idling. To prevent RPM from decreasing while the air conditioner is on, fast idle by-pass passage is provided. By-pass valve is operated by the fast idle solenoid.