I've notice what appears to be a leak at the area of the head gasket. Not sure if thats exactly where its coming from but my question is this; what symptoms would I see if it were the head gasket? Would any leaks be combined with oil and antifreeze? And it may even be a leaking thermostat, although a couple of times I noticed a small puddle of coolant on my driveway. Any advice is appreciated. BTW its a C223T engine.