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Fast Idle

  1. Set parking brake and block drive wheels. Warm engine to normal operating temperature and install Tachometer (J-26925). Air cleaner must be in place and all accessories turned off.
  2. Remove connector from fast idle solenoid. Connect an insulated jumper wire from battery positive terminal to solenoid terminal to energize solenoid. Open throttle to ensure plunger is fully extended.
  3. Adjust fast idle speed by turning plunger hex head. Adjust to specifications. See IDLE SPEED (RPM)  specifications table. Turn off engine. Remove jumper wire and test equipment. Install fast idle solenoid connector.
Fig 1: Idle Speed Adjustment
G11498Courtesy of GENERAL MOTORS CORP.
IDLE SPEED (RPM)

Application Curb Idle Fast Idle
6.2L 650 800
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