Hey JC==I would first take BOTH battery cables off and clean BOTH ends. Make sure there is a good ground between the engine and body. Then go to Auto Zone or another parts store and have the battery and starter checked out. Goodluck Joe
are they the factory locks?? if so it could bea vaccum line it operates on vaccum lines. or it could be the ground.
In the valve cover right I think.
Sounds like it could be a possible bloked heater matrix try removeing connecting hoses a jet-wash the matrix out both through the inlet and outlet until water flows free. The motor for the temperature door in the plenum isn't working. As you increase the temperature control on the dash, it sends a signal to a motor which opens the door to the heater core. Yours is sealing off the heater and allowing AC or fresh air only.