I have a 1990 Grand Prix and it says i have low coolant but there is plenty of coolent in it and my temp gauge is telling me that its over-heating and my heat blows out cold air.Ive changed the thermostat and i
You need to pressurize the cooling system, and listen for where the hissing is coming from. Common coolant leak area on your car is the "quick connect" nipple on the drivers side end of the intake near the t-stat housing.
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Would you drive any better with that cell phone up your ...?!