Originally Posted by Peacesells
its leaking for sure somewhere too. would a thermostat cause that?
No but a head gasket would but I haven't heard anything about a 5th gen with a leaky head gasket yet. If the thermostat doesn't open it could cause the coolant to try to escape another way; that should be easy to pick out. Do you have a sweet smell coming from the vents or around the engine when its running and up to temperature? Any smoke? Do you see any liquid under the car where its parked?