Valve Guide Clearance

WARNING: This page is about a different car, the 2003 Nissan Pathfinder. However, it is still accessible from the selected car via links, so may be relevant.

Measure valve deflection as shown in the figure. (Valve and valve guide mostly wear in this direction.)
Valve deflection limit (Dial gauge reading):

Intake 0.24 mm (0.0094 in)

Exhaust 0.28 mm (0.0110 in)

Fig 1: Measuring Valve Deflection
Courtesy of NISSAN MOTOR CO., U.S.A.
If it exceeds the limit, check valve to valve guide clearance.
1. Measure valve stem diameter and valve guide inner diameter.
2. Check that clearance is within specification.
  Valve to valve guide clearance limit:
  
  Intake 0.08 mm (0.0031 in)
  
  Exhaust 0.1 mm (0.004 in)
3. If it exceeds the limit, replace valve or valve guide.
  
  Fig 2: Measuring Valve To Valve Guide Clearance
  Courtesy of NISSAN MOTOR CO., U.S.A.