Crankcase Ventilation System Description
Results of Incorrect Operation
A plugged positive crankcase ventilation (PCV) orifice or hose may cause the following conditions:
| • | Stalling or slow idle speed |
| • | Oil in the throttle body |
Functional Check
With these systems, any blow-by in excess of the system capacity, from a badly worn engine, sustained heavy load, etc., is exhausted into the air cleaner and is drawn into the engine.
Proper operation of the crankcase ventilation system depends upon a sealed engine. If oil slugging or dilution is noted and the crankcase ventilation system is functioning properly, check the engine for a possible cause. Correct any problems.
If an engine is idling rough, inspect for a clogged PCV orifice, a dirty air cleaner element, or plugged hose. Replace as required. Use the following procedure:
| • | Remove the PCV hose from the cylinder head cover. |
| • | Operate the engine at idle. |
| • | Place your thumb over the end of the hose in order to check for a vacuum. If there is no vacuum at the hose, inspect for the following items: |
| • | Inspect the PCV orifice in the cylinder head cover for debris or blockage. |
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