1996 Cadillac Eldorado Temperature Gauge Reads High

Reader Question
Greetings Car Dude,
My Dad Passed away last winter after a long productive life. His pride and joy (after a lifetime of Dodge Sedans) was to purchase a 1996 Cadillac Eldorado which was the dream of a lifetime after living his life on teachers salary. He told me many times how much he loved this car.

Fast forward to present: I’m driving his pride and having little joy. I’ve driven imports (read Toyota) my whole life and never had the temp gauge budge off its spot on the dial. With the El Dorado. I’ve barely left the building when the gauge shoots up where it usually levels off about mid-point on the dial.

Idling at a light for more than a couple of minutes and the temp is one zone from the red. I don’t hear the cooling fan and after I’m parked it doesn’t seem to me to be noticeably overheated, but I’m not much of a check under the hood kind of guy.

I just had the thermostat and radiator fluids changed with no change in the wildly swinging temp readings. Any chance this is normal for a GM Product?

Yours Truly and Faithfully,
Gary

Hello Gary,

Not to burst your bubble or spoil your father’s lifetime dream, but that car is NOT known for its high maintenance record. The gauge should be about half way when the engine is at normal operating temperature, which is 210 degree Fahrenheit.

The gauge should also take a few minutes to get to the half way mark once the engine has been started. You SHOULD hear the electric cooling fan coming on and off as you sit in traffic or drive at low speeds, and it should always be ON when the A/C compressor is ON.

With the engine COLD, open the hood and check the water inside the radiator, not just inside the plastic overflow jug you see on the side. Top off the radiator with plain tap water if you need to.

If you have to add more than a cup of water, you might have a leak in the system some where and you need to get a cooling system pressure test to help locate it if you can not see anything leaking with your naked eye.

I would open the hood with the engine running and wait until the engine reaches normal operating temperature then watch for the electric cooling fan to cycle on and off. Turn on the A/C and make sure the fan kicks on as well.

If you see the fan coming on, and there is plenty of coolant inside the radiator…..you might have a gauge problem, or a bad temperature sending unit telling the gauge the wrong information.

Although, I would not be surprised to see your radiator partially restricted with rust at the bottom just due to the age of the vehicle. Flushing does not really do anything to remove this rust/calcification, only radiator replacement will cure that problem.

Blessings,

Austin Davis