S-Type (X200) V8-4.2L (2005)
Vague on-center feel is characterized by little or no buildup of turning effort felt in the steering wheel as the wheel is rocked slowly left and right
within very small turns around center or straight-ahead (under 20 degrees of steering wheel turn). Efforts may be said to be 'flat on center.'
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In the diagnosis of a readability problem, it is important to understand the difference between wander and vague on-center feel.