Have a mysterious coolant leak (Liberty 2010) the last few years that nobody can find. Seems to only leak below freezing. Finally took it to dealer only to pay $1300 and problem persists. They replaced the water pump (which was only 1 year old) and I had them change some hose clamps. I changed the rad cap, did a pressure test (pressure held), added a UV dye to the coolant (can't see external leak) among other things. Seems to be lots of white smoke so I suspected a head gasket. Took it to dealer again and their report says possible head gasket or warped cylinders but it also says "no exhaust gas detected in coolant". Doesn't that mean the coolant never reaches the engine before it leaks? I keep paying them to find the actual source and they tell me it "might be" this or that and it may need a new engine and not worth repairing. Also, it takes a while before I get good heat. I pressure flushed out the heater core, its' good. I believe air is getting in from somewhere. After I purge air from the system, the air is blowing scalding hot. Then, it takes a while for the air to get hot. So, it's as if air gets in and is purged while I drive. Any help is appreciated!