Q: How to remove and install a 2002 through 2008 Toyota Solara and 2002 through 2006 Toyota Avalon's heater core?
A: First, ensure the vehicle's air conditioning system is discharged and refrigerant is properly recovered. Disconnect the negative battery cable. Removal of the heater core involves several steps, beginning with pulling back the carpeting around the heater core/evaporator housing, removing bolts and fasteners supporting the housing on both sides, and releasing retaining clips to separate the central defroster duct from the heater core housing. The cross-cowl support tube should be unbolted but not removed, and the right-side mounting bolts for the heater and blower boxes should be removed. The left-end cross-cowl tube bolts near the door pillar should be loosened, not removed entirely. From the engine side of the firewall, disconnect refrigerant lines to the evaporator and twist off coolant hoses from the heater core tubes, or cut them off if stuck. Inside the vehicle, carefully pull the heater core housing/blower case assembled toward the rear until the heater core tubes clear the firewall. Remove retaining clips securing the heater core to the housing and slide the heater core and tubes out to the left. Installation involves reversing the removal steps, using new O-rings for evaporator refrigerant connections, and ensuring all mounting fasteners for the cross-cowl support tube and heater/blower housings are tightened before reinstalling the instrument panel pad.
Q: How to remove and install a heater core on 1997 through 2001 Toyota Avalon and 1997 through 2001 Toyota Solara?
A: To remove the heater core, start by disconnecting the negative cable from the battery and draining the cooling system. Then, in the engine compartment, disconnect the heater hoses where they enter the firewall below the heater valve. Next, pull back the carpeting from the driver's side of the console area and remove the two clips and heater protector plate. Finally, remove the three screws and clamps and disconnect the heater pipes. To install the new heater core, pull it out of the heater/air conditioning unit and use new O-rings to seal the heater core pipes. Then, refill the cooling system, reconnect the battery, and run the engine, checking for leaks and proper system operation.