Why is my grand prix running cold
change the coolant thermostat before it runs too rich and wrecks the cat. ...esp if u live in CA or a state with smog inspection.
And of course make sure the cooling system is full. Sometimes you think its running cool because the heater only blows cold air. In reality it is likely running hot. Either way its bad. Top up the coolant and put in a new thermostat like Jason said. Also make sure there is no air trapped i the system. That's bad too.
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