Non Turbo

AIR System (1.5 Liter Non-Turbo):

SYSTEM OPERATION

This vehicle is equipped with an AIR system known as "Pulse Air Induction". The system is designed to reduce hydrocarbon (HC) and carbon monoxide (CO) emissions by supplying filtered air, through the air induction valve, into the exhaust manifold. When this air meets the hot exhaust gases inside the manifold, combustion continues, further oxidizing the HC and CO in the exhaust. These pollutants are then converted into carbon dioxide and water vapor. After cold start-up, and during periods of engine warm-up the additional heat energy released helps to bring the catalyst up to operating temperature more quickly. The system consists principally of the induction valve, vacuum delay valve, vacuum switching valve, air induction pipe and ECM.


AIR INDUCTION VALVE

The "Air Induction Valve" consists of two parts, the "AIR CUT" valve and the "REED" valve. The AIR cut valve is an on-off valve which is vacuum operated. When vacuum is present at the control port, the valve is on, and filtered air from the air cleaner is allowed into the reed valve portion of the unit. The reed valve is a one way check valve. It permits air to be drawn into the exhaust when manifold pressure is below atmospheric, while preventing exhaust gas from escaping through the system when manifold pressure is greater than atmospheric.

Vacuum Switching Valve:

VACUUM SWITCHING VALVE

The Vacuum Switching Valve is an electrically controlled normally closed vacuum valve. In it's closed (de-energized) state, the AIR system is turned "off". When it is energized by the ECM, the valve opens the passage between the air induction valve control port and its vacuum source, allowing the AIR system to operate.

Vacuum Delay Valve:

VACUUM DELAY VALVE

Under hard acceleration, the pressure in the intake manifold suddenly rises to near atmospheric. The vacuum delay valve slows the change in vacuum signal to the air cut valve. This prevents the air cut valve from closing suddenly, and allows air into the exhaust even during acceleration.