Chevrolet Sonic Repair Manual: Crankcase Ventilation System Inspection/Diagnosis
- Results of Incorrect Operation
-
A plugged positive crankcase ventilation (PCV) orifice or hose may cause the following conditions:
- Rough idle
- Stalling or slow idle speed
- Oil leaks
- Oil in the throttle body
- Sludge in the engine
- 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 throttle body 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 vent filter, 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:
- Plugged hoses
- The manifold port
- Turn OFF the engine.
- Inspect the PCV orifice in the cylinder head cover for debris or blockage.
PCV
...
Positive Crankcase Ventilation Hose/Pipe/Tube Replacement
Removal Procedure
Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct
Replacement.
Open the 2 positive crankcase ventilation pipe retainer clips ...
Other materials:
Drum Brake Adjusting Hardware Inspection
Warning: Refer to Brake Dust Warning.
Visually inspect the adjuster actuator spring (1) for the following conditions:
Excessive stretching
Excessive bending
Excessive corrosion
Broken
Missing
If any of the conditions listed were found, the adjuster actu ...
Evaporative Emission Canister Replacement (Steel Tank)
Removal Procedure
Remove the evaporative emission canister bracket fasteners (1).
Disconnect the purge solenoid valve electrical connector (1).
Disconnect the evaporative emission canister vent hose (2).
Disconnect the evaporative emission c ...
Fuel Tank Fuel Pump Module Replacement (Steel Tank)
Special Tools
EN-48279 Fuel Sender Lock Ring Wrench
For equivalent regional tools, refer to Special Tools.
Removal Procedure
Relieve the fuel system pressure. Refer to
Fuel Pressure Relief.
Remove the fuel tank. Refer to
Fuel Tank Replacement.
Disconnect ...
0.0052