GM Service Manual Online
For 1990-2009 cars only

Condition

Action

Engine idle speed too fast during Neutral to range shift

Adjust to correct idle speed.

Faulty throttle sensor/circuit

Repair or replace the sensor or circuit.

Faulty or sticking bleed ball in C1 position housing

Repair the transmission.

Excessive clutch running clearance

Rebuild the transmission and adjust clearances.

Incorrect shift calibration for vehicle

Install the correct calibration.

Instrument panel tachometer incorrect

Repair or replace the tachometer.

Incorrectly calibrated electronic speedometer

Calibrate the electronic speedometer.

Faulty speed sensor/circuit

Repair the circuit or replace the speed sensor. Refer to the speed sensor DTCs.

Degraded fluid

Change the transmission fluid and filter. Refer to Automatic Transmission Fluid and Filter Replacement .

Loose speed sensor

Tighten the speed sensor retaining bracket bolt. Refer to Speed Sensor Replacement .

Incorrect fluid level

Correct the fluid level. Refer to Transmission Fluid Check .

Shift adaptives not converged

Drive the vehicle until shift adaptives are converged.

Low main pressure

Repair the transmission.

Intermittent conditions

Inspect the wiring harnesses and connectors.

Loose or damaged speed gear

Tighten the output flange bolt or replace speed gear.

Sticking valves in control valve body

Overhaul the control valve body assembly.

Leaking trim solenoids

Repair or replace the trim solenoids.