Labels:text | screenshot | font | black and white OCR: FUEL INJECTION In a Gas engine, Fuel injection refers to precise metering of the fuel to each cylinder, usually near the intake value. This method of introducing fuel to the engine is superior to the carburator. IDLE JET A small orifice which admits fuel when the airflow is too small for the Main Jet to operate properly. Unlike the Main Jet, the Idle jet flow is produced by the relatively large amount of vacuum produced by the engine when the throttle is almost closed. INTAKE MANIFOLD The passage or passages connecting the carburator(s) to the cylinder intake(s), or, in the case of a Fuel Injected engine, the passage connects the Air Filter to the intake(s)