Sounds like heater core is leaking and you are losing coolant causing overheating
This is a simple fix...I just bought a 2000 Deville and had the same issue...it's your AC Drain Hose...It's clogged up with dirt and grim...all you have to do is locate it under your car...which will be near the passenger dash underneath the car...if you can get to it..just get some pliers and pinch it open...problem solved....
where is water pump located
definitions for cadillacs sedan deville 1994 codes
7, Power steering Pump, Air Conditioning Compressor, Water pump, Crankshaft, Idler, Alternator, Belt Tensioner
It sounds like you have a bad water pump. It had seized up on you and has burned the belt.
when you go through deep water
see answer given on how to change water pump on 92 deville. Same car.
Tensioner pulley for the water pump belt on the opposite side of the motor the other side, not the side with the surpentine belt.
How to replace the belt
Same exact thing happened to my '96 cadillac deville just last week. The belt actually shredded. If you look at the location of the belt (right at the lower right corner of the engine) you may decide you may not want to mess with it yourself. I didn't. I took it in to Firestone and they fixed it parts/labor for $60
If a water pump is bad they usually leak coolant
2 gallons
Front of engine---r/s underhood