Coolant temperature

2003 Park Avenue w/o supercharger; engine coolant temperature only goes to 183/185 degrees. Changed thermostat, rated at 196 but didn't change normal running temperature.
When idling for a while temperature goes to about 205, but then comes down when driving.
Is there a thermostat bypass or could the coolant temperature sensor have drifted out of calibration or could a harness connection be corroded?
I'm reading the temperature from the digital information readout and it corolates with the analog temperature gauge.
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Eddie wrote:

And both get info from the same sensor.
Take an IR thermometer and see what is shows.
--
Steve W.

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Sounds about right from what my LeSabre does. The T'stat may be open at 196, but the location of the sensor can differ and give a different reading.
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Several times I've had older vehicles (older than yours) which had problems both with the temperature gauge sensor/sender* and the thermostat. So good to verify the temperature with a thermometer.
*Some vehicles have a sensor for the engine computer and a sender for the temp gauge. Others just a sensor for both.
"Eddie" wrote in message

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