GM Service Manual Online
For 1990-2009 cars only

Condition

Action

DEFINITION: Engine idle vibration

    • Low ATF level
    • TCC solenoid valve inoperative
    •  Drive/flex plate inoperative
    • Transmission is improperly assembled
    • Engine output low
    • Lock-up clutch piston inoperative
    •  ATF pump worn or binding
    •  Lock-up shift valve inoperative
    • Set the base idle RPM in gear, to the specified idle speed. If the condition persists, adjust the engine and transmission mounts. Refer to Engine Mount Inspection for the 3.5L (L66) engine and Transmission Rear Mount Replacement .
    • Inspect the ATF level and the ATF cooler lines for leakage and loose connections. Flush the ATF cooler lines, if necessary.
    • Perform an engine output/diagnostic test to determine if the engine is operating to specification