Yeah. Replacing a thermostat is a good place to start especially at 200000 miles.
You may also want to check your fan; I don't know if you have electrical or mechanical, but if the fan is stuck on it could prevent your car from warming up normally.
Tell me: when your car has been idling for a little bit and should be at normal temperature, what happen when your turn the heat on? Is it cold or warm?
If warm, your car is probably warming up like it should but the problem lies in the coolant sensor or the gauge.
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Sunday, December 21st, 2008 AT 10:54 AM