Crankcase Ventilation System. Cadillac Eldorado 2000

For 1990-2009 cars only

Makes 🢒 Cadillac 🢒 2000 🢒 Eldorado 🢒 Engine 🢒 Engine Controls - 4.6L 🢒 Crankcase Ventilation System

Purpose

In gasoline engines, a small amount of combustion gas leaks past the piston rings, and into the crankcase. These blow-by gases pollute the air, and reduce the quality of the engine oil. The positive crankcase ventilation (PCV) system is used to circulate fresh air into the crankcase. The PCV system removes the blow-by gases, and prevents them from entering the atmosphere.


(1)	Check Valve

Operation

Primary control of the system is through the PCV valve. The PCV valve controls the flow rate of the blow-by gases based on intake manifold vacuum. The PCV valve maintains a low flow rate when intake manifold vacuum is high (i.e. deceleration, low speed driving, or idle). The PCV allows a higher flow rate to compensate for increased blow-by when the intake vacuum is low (i.e. acceleration, or high load operation). If abnormal conditions arise, the PCV system allows excessive amounts of blow-by gases to flow through the fresh air tube, and the throttle body to be consumed in the combustion process.

Results Of Incorrect Operation

A plugged valve or hose may cause:

•	Rough idle

•	Stalling or slow idle speed

•

Oil leaks

•	Oil in the throttle body and intake manifold

•	Sludge in engine

A leaking valve or hose could cause:

•	Rough idle

•

Stalling

•	Erratic idle speed


(1)	PCV Valve
(2)	PCV Valve Hose
(3)	Throttle Body
(4)	PCV Valve Hose