Water in the radiator
I have a 2006 chevy cobalt an I have to fill the
radiator with water every 2 or 3 weeks does anyone
have any clue where the water is going
If you are constantly refilling the radiator, then you have a leak somewhere. Find the leak and repair. You can rent a coolant pressure tester that puts air into the system and forces the coolant out the area where it is leaking to help find it easier. Did you check your other fluids to see if it isn't mixing with your oil or transmission fluid?
Agree. If its not showing up on the ground then its either going out the exhaust or into the engine. If its in the engine it will turn up in the oil pan and turn your oil into something that looks like a milkshake. Check your dipstick. If its going out the exhaust a cooling system pressure test, and/or a compression test should tell you where. You could try adding Bars Leak to the cooling system, but if its loosing that much coolant the leak may go beyond what that product can address. No harm in trying it though, and its a cheap "fix" if it works.
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