Variable Induction System: Description and Operation

Triple Induction Control System:

JE V-6 cylinder heads are designed with two small intake valves and one large exhaust valve per cylinder. This design optimizes torque and power by improving intake and exhaust efficiency at medium and high speeds. However, the configuration has a detrimental effect on intake airflow at low speed because intake valve area is large enough to cause a slowing of airflow as it enters the combustion chamber. To correct this deficiency, the Triple Induction Control System (TICS) causes air to flow through only one intake valve per cylinder during low speed and light-to-medium load operating conditions.

During idle, light and medium loads, the ECU energizes the TICS solenoid valve, applying manifold vacuum to the swirl control valve actuator. The swirl control valves are opened slightly and most intake air is forced to flow through small swirl ports. Air is fed directly to cylinder head swirl ports where it is directed past one intake valve and into the cylinder. The result is a strong swirl in the combustion chamber, improving combustion and fuel economy.

During medium to high speed and heavy load conditions, the ECU closes the TICS solenoid valve and vacuum is vented from the swirl control actuator. Swirl valves open and intake air flows through the intake ports into the cylinder. At this time, the advantage of the three-valve design is realized.

To calculate TICS operation, the ECU utilizes input information from distributor signals for engine speed and crankshaft position and the airflow meter for throttle position.