CEL Code P0128
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2019 C63CS
Take the car in. This might be related to your earlier CEL. P0128 means your engine isn't reaching operating temperature as it should. Could be the thermostat stuck open or opening prematurely or your coolant temperature sensor not working.
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Yeah, that's normal. I was at 194 after a lap around the Nurburgring for example. It's in that neighborhood. As long as the temperature is indicated in white, it's within normal operating range. Blue is too cold, and red is too hot.