Variable Induction System: Description and Operation

Power Valve Control Input/Output Signal Line:

PURPOSE
The power valve system is used to provide a variable length of intake run.





OPERATION
When the engine is running at a low to medium rpm with a heavy load, the Engine Control Module (ECM) energizes the power valve solenoid. The solenoid allows manifold vacuum to act upon the power valve diaphragm, closing the power valve. This increases the length of the intake runner which results in higher engine torque.

When a longer intake run is not needed the power valve is left open to allow a shorter air intake path. This results in improved engine performance in the higher rpm range.

A surge tank and one-way valve is provided to store vacuum so that the valve will remain closed during low manifold vacuum conditions.