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Car Running Hot

I intend to bring our car to the shop, but before I do, I’m curious about what could be making an older car (a 1995 Chrysler Concorde) run “hot” or “high.”
I think the temperature gauge needle climbs too high, even though the car doesn’t actually overheat. It also smells too hot after driving just a few miles. Probably most tellingly, the engine sounds like it’s running too high – even when just idling, it sounds almost like it’s being revved.

Thank you!

Most likely culprits are a bad radiator cap. Low Coolant Level, A leak in the system causing it not to pressurize, bad coolant overdue for a flush, clogged arteries in the radiator.

Here’s some ideas

Coolant level is low, radiator cap needs replacement, radiator cooling fan isn’t working, thermostat isn’t opening fully, and there’s other more difficult to fix stuff. Cross your fingers it is not that.

In the meantime, monitor the coolant temp. If it starts to overheat, turn on the heater to max and the heater fan to max. That will provide you some engine cooling. If it goes into the red zone, stop and have the car towed to a shop.

Check the coolant level.
Check for leaks.
Make sure all of the fans are operating.
Make sure the accessory drive belt isn’t loose and/or glazed.

If all of the above is okay, replace the cap and thermostat.

Nobody mentioned that, for safety, you should let the engine cool down completely before removing the radiator cap. To be sure, check it in the morning before you first start the car. If you don’t see coolant in the radiator, fill it, also fill the overflow reservoir to the proper level, and check it again the next time the engine is cool…the level may go down simply because there was air in the water jacket.

If the radiator and overflow are at proper levels, try to notice what conditions cause the temp gauge to rise. If you find that it’s hot in slow city driving, but cools down on the highway, then that points toward the cooling fan not operating, though this is not an absolute.