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Closed Crankcase Ventilation System

  1. Closed Crankcase Ventilation (CCV) system is used on both the 2.4L and 4.0L engines. CCV system performs same function as a conventional PCV system, but does not use a vacuum controlled PCV valve. CCV system uses a fixed orifice fitting. See Fig 1. Ensure locations of fixed orifice fitting and air inlet fitting have not been exchanged.
  2. Fixed orifice fitting is Light Gray in color and the air inlet fitting is Black in color. On 2.4L, the fixed orifice fitting is located on left front side of valve cover and the air inlet fitting is located at the rear of valve cover. See Fig 2. On 4.0L, the fixed orifice fitting is located at the rear of valve cover and the air inlet fitting is located at the front of valve cover. See Fig 3.
  3. On all models, remove fixed orifice fitting from valve cover and leave tube attached. Start engine and let idle. A hissing noise should be heard from fixed orifice fitting. Also, a strong vacuum should be felt with a finger placed at fitting inlet. If vacuum is not present, remove fitting. If vacuum is now present at tube, replace fixed orifice fitting. Do not attempt to clean fitting. If vacuum is not present at tube, go to next step.
  4. Check tube for kinks or obstruction. Clean tube fitting at intake manifold, if necessary. A 1/4" drill may be used (by hand) to dislodge any solid particles. Reinstall fixed orifice fitting and tube. Disconnect air inlet fitting and hose from front of valve cover.
  5. Hold a piece of stiff paper loosely over opening in valve cover. Allow engine to idle for one minute. Paper should be drawn against rubber grommet in valve cover by vacuum in crankcase. If vacuum is not present, check tubes for restrictions or obstructions.
Fig 1: Identifying Fixed Orifice Adapter
G00010253Courtesy of DAIMLERCHRYSLER CORPORATION
Fig 2: Locating Closed Crankcase Ventilation Components (2.4L)
G00010246Courtesy of DAIMLERCHRYSLER CORPORATION
Fig 3: Locating Closed Crankcase Ventilation Components (4.0L)
G00010249Courtesy of DAIMLERCHRYSLER CORPORATION