Notes On Intermittents

WARNING: This page is about a different car, the 1995 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.

Code is not set by vacuum leaks or vacuum supply problem. Code can only set when vehicle speed exceeds cruise control set speed by 20 MPH.

Fig 1: Code P063 Schematic, Vehicle Speed & Set Speed Difference

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code P063 Diagnostic Flow Chart, Vehicle Speed & Set Speed Difference

Courtesy of GENERAL MOTORS CORP.