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:
Park Brake Hardware Inspection
Warning: Refer to Brake Dust Warning.
Visually inspect the park brake lever (1) and the lever pivot pin (2) for
the following conditions:
The lever being bent or broken at any point – particularly at the cable
attachment
A seized or binding condition ...
Tire Terminology and Definitions
Air Pressure
The amount of air inside the tire pressing outward on each square inch
of the tire. Air pressure is expressed in kPa (kilopascal) or psi (pounds per
square inch).
Accessory Weight
The combined weight of optional accessories. Some examples of optional
access ...
Turbocharger Wastegate Regulator Solenoid Valve Replacement
Charge Air Bypass Regulator Solenoid Valve Replacement
Callout
Component Name
Preliminary Procedure
Disconnect the radiator outlet hose from the water inlet. Refer to Water
Inlet Replacement.
1
...
0.0096