WARNING: This page is about a different car, the 2005 Nissan 350Z. However, it is still accessible from the selected car via links, so may be relevant.

Pull negative-pressure valve to open it and make sure that it closes completely when released.
- Make sure that there is no dirt or damage on the valve seat of radiator cap negative-pressure valve.
- Make sure that there are no unusualness in the opening and closing conditions of negative-pressure valve.
Fig 1: Pulling Negative-Pressure Valve
Courtesy of NISSAN MOTOR CO., U.S.A.
Check radiator cap relief pressure.
- Standard:
  - Torque Specification :78 - 98 kPa (0.8-1.0 kg/cm ² , 11-14 psi)
- Limit:
  - 59 kPa (0.6 kg/cm ² , 9 psi)
- When connecting radiator cap to radiator cap tester (commercial service tool) and radiator cap tester adapter [SST], apply engine coolant to the cap seal surface.
  
  Fig 2: Checking Radiator Cap Relief Pressure
  Courtesy of NISSAN MOTOR CO., U.S.A.
- Replace radiator cap if there is an unusualness in negative-pressure valve, or if the relief pressure falls below the limit.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Checking Radiator Cap

Use the Manual With the Right Hardware

When to See a Mechanic