Pickup 1997

Positive Crankcase Ventilation System

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PCV Valve



Location

Specific to:

Nissan Pickup 1996-1997



Click image to see an enlarged view

Fig. PCV system schematic

Operation

Specific to:

Nissan Pickup 1996-1997

The PCV system consists of the breather tube and the PCV valve. The breather tube connects the crankcase to a contained fresh air source such as the air cleaner. Air passes into this tube and into the engine after being filtered through a spark arrestor screen in order to prevent a the possibility of an explosion within the engine in the case of a backfire.

Removal & Installation

Specific to:

Nissan Pickup 1996-1997

At this time the manufacturer does not provide removal and installation procedures for this component. The following procedure is a guideline and may differ from the vehicle you are servicing.

  1. Before servicing the vehicle, refer to the Precautions Section.
    NOTE
    If working near and/or around the SRS system and components, be sure to disable the SRS system. After disabling the system wait three minutes or more before servicing the vehicle. Disconnect the air bag module connector.



    Click image to see an enlarged view

    Fig. Air bag module connector location

  2.  
  3. Disconnect the negative battery cable.
  4.  
  5. Remove the necessary components to gain access to the PCV valve.
  6.  
  7. If not already done, detach the ventilation hose from the PCV valve.
  8.  
  9. Remove the PCV valve. If its base is threaded, unscrew the valve; otherwise, simply pull the valve from its retaining grommet.

    Click image to see an enlarged view

    Fig. PCV system schematic

  10.  

To install:


NOTE
Be sure to use new fasteners, as required.

  1. Installation is the reverse of the removal procedure.
  2.  
  3. Depending on the type of valve, either screw in the replacement PCV valve or push it into its retaining grommet.
  4.  
  5. Slide the ventilation hose onto the end of the PCV valve.
  6.  
  7. Using the CONSULT-III diagnostic tool, or equivalent, perform the SRS self diagnostic test and any reconnect/relearn procedures, as required.
  8.  

Testing

Specific to:

Nissan Pickup 1996-1997

  1. Check the ventilation hoses and lines for leaks or clogging. Clean or replace as necessary.
  2.  
  3. With the engine running at idle, locate the PCV valve in the cylinder head cover or intake manifold and remove the ventilation hose from the valve; a strong hissing sound should be heard as air passes through the valve.
  4.  
  5. With the engine still idling, place your finger over the valve; a strong vacuum should be felt.
  6.  
  7. If the PCV valve failed either of the preceding two checks (and the ventilation hose is not clogged or broken), the valve will require replacement.
  8.  

Check the PCV valve, system hoses, retaining clamps and connections, to see that there are no leaks. Then replace or tighten, as necessary.

Check all hoses and connections for leaks. Disconnect all hoses and clean them with compressed air. If the hose cannot be freed of its obstruction with the force of air, replace the hose.

To check the valve, remove it and blow through both of its ends. When blowing from the side which goes toward the intake manifold, very little air should pass through it. When blowing from the crankcase (cylinder head cover) side, air should pass through freely.

An additional check without removing the valve could be with the engine running, remove the ventilator hose from the PCV valve. If the valve is working, a hissing noise will be heard as air passes through the valve and a strong vacuum should be felt immediately when the valve inlet is blocked with a finger. If the valve is suspected of being plugged, it should be replaced.

Replace the valve with a new one if the valve fails to function as outlined.

After removing the PCV valve shake it end to end, listening for the rattle of the needle inside the valve. If no rattle is heard, the needle and valve is jammed. Do not attempt to clean or adjust the valve, replace it.

 
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