The heater core on a 1996 Caprice Classic is a part of the cooling system on the engine, as well as the heating system for the climate control system. It runs coolant through its core, which creates heat that is sent out through the vents. If this core breaks, then coolant will leak into the inside of the cab, which will cause a mess and could overheat the engine. To fix the issue, you can remove the heater core and install a new one in its place.
Let the engine of the Caprice cool down until you can grab a radiator hose with your hand and not recoil from the heat. Locate the two heater core ports on the passenger side of the firewall. Remove the hose clamps attaching the lines to the heater core ports, then install the plugs on the heater core ports.
Open up the passenger side door. Unbolt the lower dash trim from the passenger side of the dashboard, as well as the glove box, using the 3/8-inch ratchet and socket. Unplug the vacuum lines leading to the heater core with your hands.
Unbolt the lower instrument panel brace from the dashboard and the heater core clamp bolt with the 3/8-inch ratchet and socket, then pull the heater core out from under the dashboard. Install the replacement heater core in the dashboard with the 3/8-inch ratchet and socket, then reinstall the lower instrument panel brace to the dash with the ratchet.
Reinstall the vacuum lines on the heater core assembly, then reassemble the dashboard and glove box with the 3/8-inch ratchet and socket. Attach the heater core hoses to the heater core ports in the engine bay with the flathead screwdriver.
Open the radiator cap on the radiator and fill the radiator with the 50-50 pre-diluted coolant. Reinstall the radiator cap. Start the Caprice Classic's engine.Turn the heater controls to the highest position and check for leaks underneath the glove box and heater core. Let the engine reach normal temperature, then turn off the engine. Let the engine cool, then open up the radiator cap and fill with any 50-50 pre-diluted coolant that may be needed. Reinstall the radiator cap.
