why is my car runing hot
Could be lots of things, but most likely is low coolant level. The 3.8 which I assume you have is notorious for gasket failures which cause coolant loss either externally or internally. Often the coolant loss is very gradual. If you find the level is low, top it up with the correct coolant and add a unit of Bars Leak to your system. It's very effective in solving minor leaks and saves you the considerable work and expense of changing gaskets on an old car. Second would be to change the thermostat. They don't last forever and will cause overheating if they are stuck closed. Be sure to bleed all the air out of the system after you change it (or if you add a lot of coolant to a low system) as air trapped in the cooling system will also cause overheating problems.
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