Test Conditions
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.
Codes P021, P022 and P024 not set. Vehicle in coast down condition. Throttle position switch open, brakes applied, throttle angle 16.5 degrees or less, and engine speed at least 64 RPM greater than desired. At least 4 seconds have passed between brake applications or the last ISC motor pulse from PCM.