GM Service Manual Online
For 1990-2009 cars only

Checks

Cause

Governor (4)

    â€¢ Springs are distorted or out of place
    â€¢ Governor weights are binding on the pin

Control Valve Assembly (21)

    â€¢ The 1-2 shift valve is sticking in the upshifted position (320)
    â€¢ The 1-2 throttle valve is sticking in the upshifted position (321)