passenger side front wheel well
Heater hose or heater core.
The water pump for a 1998 Cadillac catera should be on the front of the engine. It is located near the center.
Oil cooler is bad.
no just one
"http://wiki.answers.com/Q/Where_is_the_hot_water_control_valve_on_the_Cadillac_catera_located"
Follow the top radiator hose down to the water outlet on the engine. It is in the outlet.
one way is the headgasket is blown oil can leak into the water jackets and get wixed with the oil
It is on the front of the engine. It is not a job for a backyard meahcnic.
just mehanical and yes its fairly easy
if its under the dash by your feet its the heater core is bad
Keeps engine coolant from going through heater core when it is not needed.
Pressure test system to determine where leak originates to repair Water Control Valve, on pass. side behind engine.