Originally Posted by weasel56

With the plastic cover removed from the engine, look with a flashlight at the back of the engine between the manifold and head. If it is the valley pan leaking, you should see either some coolant or signs of leaking. Anywhere on the cooling system that has what looks like corrosion buildup, like at the ends of the hoses, etc. would be a tiny leak, where the coolant is leaking soo slow it evaporates away before having a chance to drip.