GM 91172080 Receiver

For pre-1999 models, begin by discharging the air conditioning system and disconnecting the negative battery cable. Unplug the electrical connector from the pressure switch located near the top of the A/C Accumulator, then remove the bolts and disconnect the refrigerant lines from the top of the A/C Accumulator. To prevent dirt and moisture from entering, plug the open fittings. Loosen the mounting bracket pinch bolt and lift the A/C Accumulator out. If installing a new A/C Accumulator, remove the Schrader valve and pour the oil into a measuring cup, noting the amount, then add fresh refrigerant oil to the new unit equal to the amount removed plus one ounce. Installation follows the reverse order of removal, and afterward, take the vehicle back to the shop for evacuation, charging, and leak testing. For 1999 and later models, the A/C Accumulator is welded to the condenser and cannot be replaced separately, but the filter and dryer elements can be replaced. Have the system discharged by a dealer or automotive air conditioning shop, then remove the condenser. Unscrew the plug from the top of the A/C Accumulator unit and pull out the filter and drier using long needle nose pliers. Before installing a new drier, add 40 cc of refrigerant oil and do not remove it from its plastic bag until just before insertion. Ensure the double-layer portion of the new drier faces down when inserting it into the A/C Accumulator unit. Installation is otherwise the reverse of removal, and once completed, have the system evacuated and recharged by a dealer or automotive air conditioning shop.