Cadillac Repair: heater, cylinder head gasket, seal tabs

Question
my 92 deville has new radiator,water pump,heater core,thermostatand cap.my local radiator shop is now going to flush out the heater core to try and get heat.                                    do you have any thing else I can tell them to check?                  it does have climate cotrol.

Answer
Hi John, With all those parts being replaced the anti-freeze level should be ok and any air pockets purged out. A new thermostat could be bad and opening too soon. The cooling fans should be off. Heater cores do get plugged up because of the seal tabs that Cadillac recommends be used in the cooling system. If the hoses at the heater core feel hot then it is time to go inside the car and remove the glovebox and see if the programmer is able to move the arm all the way to hot. I have seen a wire get pulled out of the motor connector, motor gears stripped out midway through its travel and bad temp sensors that don't allow the arm to move to the full hot position. After that there is a possibility the cylinder head gasket could be leaking but the temp light should be on along with cold-hot-cold-hot air from the vents. In other words there will be hot air but will cool down with-in 4 minuits and then heat up again. I would think flushing the heater core or replacing it will give you the heat you are looking for. Hope that helps. Bill