Q: How to remove and install an evaporator and expansion valve in a Toyota Solara and Toyota Avalon air conditioning system?
A: To remove the evaporator in your air conditioning system, follow these steps. First, have the air conditioning system discharged and recovered, then disconnect the cable from the negative battery terminal. Disconnect the receiver line and suction line from the evaporator and plug both lines to prevent contaminants and moisture from entering the system. Drain the coolant and disconnect the heater hoses at the firewall. Remove the dashboard trim panels and the dashboard itself. Disconnect the electrical connectors from the blower housing and evaporator housing. The blower housing must be removed before the evaporator housing. Remove the connecting duct between the two units, along with the mounting bolts and screws, to take out the blower unit. Remove the bolts holding the A/C Expansion Valve to the evaporator core. Remove the two rear heating ducts and the fasteners retaining the evaporator housing to the firewall. Disconnect the drain hose and carefully remove the evaporator unit from the vehicle. Also, remove the thermostat sensor from the evaporator. Finally, remove the screws, separate the housing, and extract the evaporator. For installation, follow the reverse order of removal, ensuring new O-rings are installed and coated with R-134a refrigerant oil. Once installed, have the system evacuated, charged, and leak tested. If a new evaporator was installed, add 1.4 ounces of new refrigerant oil.