After I changed the engine on my Civic DX a couple of years back my car started overheating, leak somewhere. Took me a week to find the leak because there was no wetness anywhere. So one day I came home from worked and parked the car and popped the hood. I left the car running for whatever reason and out the corner of my eye, saw a very, very, fine stream of fluid. Turns out one of the coolant hoses on the IM had a very minute pin size hole and the coolant would only spray out when the car was at operating temperature and the coolant started flowing thru the system. And the kicker was that the coolant only squirted out in short pulses. So If you looked and turned away you would have never saw the leak.
