2004 Chevy Monte Carlo gauges and heater

2004 CHEVROLET MONTE CARLO
60,000 MILES • 6 CYL • FWD • AUTOMATIC
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CBENTZ50
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  • 1 POST
My temp gauge and speedometer are not working properly. The temp gauge is always showing that the engine is running hot, the speedometer does not always register the speed. Sometimes the speedometer reads 50 or 60 when the car is idle. The heater is only expelling cold air until the engine is warm. After the engine heats up the air is warmer but not as hot as it should be.
Nov 27, 2009 at 3:13 PM
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JACOBANDNICKOLAS
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If I had to guess, I would say the two things are not related. Are you sure the coolant is full? Also, when the engine is running, hot, and the heater on high, are both heater core hoses hot? Finally, has the coolant ever boiled over?

As far as the speedo, it sounds like there is a problem with the vehicle speed sensor (VSS). It is the sensor that tells the speedo how fast the car is moving. Many times it will set a "Check Engine" light. Has that ever happened?
Dec 5, 2009 at 7:23 PM
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