GM Service Manual Online
For 1990-2009 cars only

Condition

Possible Cause

Correction

Blower Motor Noise

    â€¢ Foreign material is on the fan.
    â€¢ The fan blades are broken or missing .
    â€¢ The blower motor has internal damage.
    â€¢ Remove the material. Reuse the blower motor if possible.
    â€¢ Replace the motor and fan assembly.
    â€¢ Replace the motor and fan assembly.

A/C Compressor Noise

    â€¢ The compressor mounting bracket fasteners are not torqued to specifications.
    â€¢ The compressor mounting fasteners are not torqued to specifications.
    â€¢ The A/C compressor pulley bearing is faulty.
    â€¢ The belt slips.
    â€¢ Inspect the compressor bracket to engine torque.
    â€¢ Inspect the compressor to bracket torque.
    â€¢ Replace the A/C compressor pulley and bearing.
    â€¢ Inspect the belt tensioner, the idler pulley and/or the belt.

A/C Refrigerant Lines/Hoses Noise

    â€¢ The lines or hoses are grounded.
    â€¢ The lines or hoses rub on the other components.
    â€¢ Reposition the A/C lines or hoses.
    â€¢ Reposition and secure the lines and hoses.

HVAC Module Noise

    â€¢ Foreign material is in the A/C module.
    â€¢ The A/C module is not torqued to specifications.
    â€¢ The actuator door is damaged.
    â€¢ Remove the material from the case.
    â€¢ Torque the A/C module to specifications.
    â€¢ Repair or replace the door(s).