All,
Below is a copy and paste from my 2.0L manual. Not sure if anyone is interested.
CRANKCASE VENTILATION SYSTEM INSPECTION/DIAGNOSIS
1. Disconnect the positive crankcase ventilation (PCV) line.
2. Start the engine.
3. Check for vacuum at the PCV line. If there is no vacuum, inspect for a plugged line or
camshaft cover port. Inspect for a hose that collapses when blocked with vacuum applied.
Replace the plugged or the deteriorated hoses.
4. Allow the engine to idle at normal operating temperature.
5. Remove the engine oil level indicator. Install a vacuum gage into the indicator tube opening.
6. Block off the PCV system fresh air intake passage.
7. Run the engine at 1,500 RPM for 30 seconds, then read the vacuum gage while engine is
running at 1,500 RPM.
If vacuum is present, the crankcase ventilation system is functioning properly.
If no vacuum is indicated, the engine may not be sealed and is drawing in outside air.
Check the valve covers, the oil pan gasket, or other sealing areas for leaks.
If the vacuum gage registers a pressure, or if the vacuum gage is pushed out of the
indicator tube, check for a plugged PCV port, a plugged line, or excessive engine
blow-by.
CRANKCASE VENTILATION SYSTEM DESCRIPTION
General Description
A crankcase ventilation system is used to consume crankcase vapors in the combustion process
instead of venting them to atmosphere. Fresh air from the intake system is supplied to the
crankcase, mixed with blow by gases and then passed through a calibrated orifice into the intake
manifold.
Operation
The primary control is through the positive crankcase ventilation (PCV) orifice which meters the
flow at a rate depending on inlet vacuum. The PCV orifice is an integral part of the camshaft
cover. If abnormal operating conditions occur, the system is designed to allow excessive amounts
of blow by gases to back flow through the crankcase vent into the intake system to be consumed
by normal combustion.
On the turbocharged engine, there is a one way valve in the intake manifold in order to prevent
the crankcase from being pressurized by positive pressure in the intake manifold when the
turbocharger is in operation. When the turbocharger is operational, the pressure in the intake
manifold can exceed atmospheric pressure which, without the one way valve, would force oil and
PCV gases out of the camshaft cover and into the induction system, via the hose to the camshaft
cover. This can cause coking of the throttle body and induction system, and can reduce the
efficiency of both combustion and the intercooler system, in normal operation the PCV gases are
drawn into the air stream post intercooler.
