Valve Spring Squareness

WARNING: This page is about a different car, the 2005 Infiniti QX56. However, it is still accessible from the selected car via links, so may be relevant.

Set try square along the side of valve spring and rotate the spring. Measure the maximum clearance between the top face of spring and try square.
1. Limit: Less than 2.2 mm (0.087 in)
If measurement is not within specifications, replace the valve spring.

Fig 1: Measuring Maximum Clearance Between Top Face Of Spring And Try Square
Courtesy of NISSAN MOTOR CO., U.S.A.