The A/C compressor in your Pontiac Sunfire circulates R-134a refrigerant through the system so that the two changes of state that are required for proper A/C function can occur. When the compressor fails, the refrigerant no longer circulates, and the A/C system stops cooling. Removal and replacement of the compressor can be done by the average home mechanic with basic hand tools after the refrigerant has been recovered from the system by a certified automotive technician.
Disconnect the negative battery cable with an 8 mm wrench and set it aside. In the Pontiac Sunfire, the battery is located at the front of the engine compartment on the driver's side in front of the air filter housing.
Remove the serpentine belt by rotating the belt tensioner counterclockwise with a serpentine belt tool. The tensioner on the Sunfire is located on the front of the motor between the power steering pump pulley and the crankshaft pulley. The proper routing of the serpentine belt is shown on a decal located on the radiator support. If the decal is missing or cannot be read, make a quick sketch of how the belt is routed before you remove the belt.
Unplug the alternator electrical connector then unscrew the charging post nut on the back of the alternator with a 10 mm wrench. Set the wiring aside.
Remove the 13 mm bolts and nuts that attach the alternator to the engine with a socket and ratchet. Rotate the alternator toward the front of the car and lift it from the engine compartment.
Unscrew the 15 mm A/C compressor line bolt from the back of the compressor with a socket and ratchet then set the lines aside. Remove the 13 mm bolts that attach the compressor to the engine with a socket, ratchet and 3inch long extension. Slide the compressor toward the front of the car and lift it from the engine compartment.
