Checking Reservoir Cap

WARNING: This page is about a different car, the 2005 Nissan Frontier. However, it is still accessible from the selected car via links, so may be relevant.

Inspect the reservoir cap.
- Replace the cap if the metal plunger cannot be seen around the edge of the black rubber gasket.
- Replace the cap if deposits of waxy residue or other foreign material are on the black rubber gasket or the metal retainer.
NOTE: Thoroughly wipe out the reservoir filler neck to remove any waxy residue or foreign material.
Pull the negative-pressure valve to open it and check that it closes completely when released.
- Check that there is no dirt or damage on the valve seat of the radiator cap negative-pressure valve.
- Check that there are no abnormalities in the opening and closing conditions of the negative-pressure valve.
  
  Fig 1: Pulling The Negative-Pressure Valve To Open
  Courtesy of NISSAN MOTOR CO., U.S.A.
Check reservoir cap relief pressure using Tool.
Tool number : EG17650301 (J-33984-A)

Standard: 98 - 118 kPa (0.99 - 1.20 kg/cm ² , 14 - 17 psi)
- When connecting the reservoir cap to the tester, apply water or coolant to the cap seal surface.
- Replace the reservoir cap if there is an abnormality in the negative-pressure valve, or if the open-valve pressure is outside of the standard values.
  
  Fig 2: Checking Reservoir Cap Relief Pressure
  Courtesy of NISSAN MOTOR CO., U.S.A.