something with my Tempnow my thermostat is going crazy, it goes up to the red and then back down, when i drive it stays down, if i sit in traffic it starts to overheart, I do have a coolant leak, had it for 1 year and no mechanic can ever find the leak, also my heat is not workingI will be taking it to a mechanic today but wanted someone opnion of what it could be and how much you think the cost will be
Low coolant or air in the coolant system, will cause the vehicle to overheat, heater not to work, and erratic temp gauge. So that answers your currant symptoms. Do you have the 3.4 liter v6? If so, the coolant system needs to bleed after you fill the coolant. Looking at the motor, there should be a bleeder on the passenger side, front by the belt. There might be another one on the driver side by the thermostat. Loosen these, fill with coolant. Start the car and let it warm up. While it is warming up, you will see coolant, and air sputtering out of these bleeders. Wait until it is a solid stream of coolant, then close them. Top off the coolant and you are done. Now where is the coolant going. If it is the 3.4 v6 the motors are infamous for intake gaskets, and head gaskets going bad. Check the oil, to see if coolant is showing up in there. If not do a compression test on the motor. Willing to bet that head, or intake gaskets are bad, and that is where the coolant is going. If it is deemed the intake gaskets are bad, might as well spend the extra and have the headgaskets changed. You will save in the long run. Hope it goes well.
Please take the car to a Chevrolet dealer! If the cooling system has never been drained flushed and cleaned do not trust just anyone to do this. They'll do a cooling system pressure test which will find the external or internal coolant leak. The moron at Advance Auto didn't overwhelm you with any kind of answer.
In My opinion sounds like a Heater Core is out ( Basically a small Radiator like piece that gets Plugged up) Usually found on the Passenger side with Two medium sized rubber hoses going into it. Quite easy to change. If that's not the problem could be as simple as the thermostat, i always check the small simple things first because this is the best way to trouble shoot. Nine times out of ten its always the the small simple cheap things.
