Scheme 275
Scheme 276
- After disconnecting the vapor hose from the PCV valve, remove the PCV valve.
- Reconnect the PCV valve to the vapor hose.
- Run the engine at idle, then put a finger over the open end of the PCV valve and make sure that intake manifold vacuum can be felt. NOTE: The plunger inside the PCV valve will move back and forth at vacuum.
- If the vacuum is not felt inspect PCV operation, if operating correctly clean or replace the vapor hose.
Operation Principle
PCV OPERATION CHART Engine Condition Not Running Idling Decelerating Normal Operation Accelerating and High Vacuum in intake Manifold 0 High Moderate Low PCV Valve Close Slightly Open Properly Open Fully Open Blow-by Gas Flow 0 Small Medium Large Schematic Diagram Intake Manifold Intake Manifold Intake Manifold Intake Manifold