Intake Manifold Swirl Valve
A swirl and a charge inlet port are provided in the intake manifold for each cylinder . The charge inlet port can be closed by means of flaps. The flaps are connected to each other by means of a linkage, which is operated by the swirl valve actuator . They are held in the open position by means of spring force.
In the lower engine speed and load range all the charge inlet ports are sealed off by the flaps. The entire air flows through the swirl inlet ports only. This results in high air swirling which in turn produces more effective mixing of the fuel with the air, which improves combustion and reduces the amount of soot particulants in the exhaust.
As engine speed and loads rise, the charge inlet ports are continuously opened to obtain the best possible ratio between air swirling and air mass for each engine operating point, which will optimize exhaust characteristics and engine power output.
The position of the flaps in the charge inlet ports is determined by the map stored in the Engine Control Module (ECM). The swirl valve actuator is actuated by the swirl valve actuator solenoid. This is a PWM solenoid.
| 1 - CHARGE INLET PORT |
| 2 - FLAP |
| 3 - VACUUM PORT FROM SOLENOID |
| 4 - SWIRL VALVE ACTUATOR |