Electronic Controlled Carburetor (ECC)

The air cleaner removes dust and dirt from the air before it enters the carburetor and muffles the noise created by air intake into the engine. When underhood air temperature is low, the automatic temperature control system maintains suction air at a specified temperature to enable lean carburetion calibration, thereby reducing the emission of hydrocarbons. This system also enhances warm-up characteristics of the engine and helps to eliminate carburetor icing.
This system consists of a fresh air duct, hot air duct, air inlet pipe, vacuum motor, air control valve, temperature sensor, blow-by gas filter, and air filter. An idle compensator is incorporated into the air cleaner housing and operates independently to provide smooth engine operation during idle. There are also various vacuum hoses routed to the housing which connect to independent emission control systems.
This system is controlled by the inlet air temperature and the load condition of the engine. The inlet air temperature is detected by the sensor and the vacuum motor is activated by intake vacuum.
When underhood air temperature is low the sensor air bleed valve remains closed, establishing vacuum passage between the intake manifold and vacuum motor. At this time, intake manifold vacuum activates the air control valve to introduce hot air into the air cleaner through the hot air duct on the exhaust manifold. When vacuum is minimal or when the engine is operating under a heavy load, the air control valve opens fully regardless of the air temperature around the sensor to introduce the cooler air for increased engine power.
When underhood air temperature is high, the sensor air bleed valve opens fully to shut off vacuum passage between the intake manifold and vacuum motor. Due to the force of the vacuum motor spring, the air control valve closes the hot air pipe of the air cleaner and introduces the cooler air.
When ambient temperature around the sensor causes it to partially open air bleed valve, air control valve operation is controlled by intake manifold vacuum. When the air control valve is partially open, both hot and cold air are introduced into the air cleaner as a mixture.