Question about 1999 Cadillac DeVille

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Over heating/ loss of coolent

My 1999 Deville, over heats!! Before you answer let me tell you what I have done.. I have repalced Raidator, Evaporator core, Overflow tank, Pressure cap, and Thermostat.

It steal losses coolent & overheats.. The only thing I have't done is replace Water Pump... Please Help!!!

Thank you for your Time ! DC

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  • Anonymous May 11, 2010

    Has any one heard of Heal -A -Seal. Out of Calf. If so does it work....

    Thanks DC



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If you are not loosing coolant on the ground. You may have a problem of a bad intake manifold gasket or worst a bad head gasket. The two things to look at are coolant in your oil, manifold gasket. Coolant out the exhaust, head gasket.

Posted on Jul 05, 2008

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I got a 99 cadillac devielle n it do not run hot but i cant get no heat im the inside of my body

Posted on Jan 21, 2012


I have a 99 DeVille that was losing coolant and needed topping up every month or so. I just gave it the Thermagasket treatment (see rxAuto) and it worked for me.

I know many mechanics think this is rubbish. Even mine felt the same way. However it worked for me so far (250 miles since treatment).

This weekend it gets the real test as we are going to the same hill that gave us a "Coolant temperature to hot" warning. It's sure a lot cheaper than a new engine or a head gasket job. Besides the Northstar engine has a well known problem with the head bolts stripping the threads.



Posted on Jul 24, 2008

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