Thanks for the reply. When you say run with cap loose, if leak slows or stops, then I've confirmed that it is coolant - (Is that what you mean - or am I missing a step) Reason I ask is it really does smell like coolant, I have cleaned up the areas on the floor, and got a good look and smell, (so to speak). leaks ONLY on passengers side down trans tunnel side. Read a post (this forum) about a heat exchanger in near windshield under wiper arms (area) that could leak - this is a California model - I don't know if there is one - I am guessing this was OPTIONAL? Thanks again. Steve As far as the trans tunnel area - to start looking - should I take a look behind radio and ACC unit first or go behind under dash?