I think trying to find a water leak in any car is really difficult right along with finding that elusive rattle that has at times pervaded a few of us I think at one time or another. So I’ve got one-the rattle-from evidently underneath the brick; well it almost sounds like a loose muffler/hanger but it's not. Also it’s only evident when the car is first started up cold-like after sitting all night. It sorta sounds like a muffler with something loose inside of it but the strange thing again is once the car is even slightly warmed up the rattle disappears. The mufflers seem to be in good shape and the cat was replaced 2 years ago. All the pipes look fine and as I said the hangers are tight, and anyway why would the rattle go away after engine warm up? Once the car has been started, then starting it again before it's cooled way down, then there is no rattle on the startup. . So-if it's not in the exhaust system, well, any ideas from what I’ve described? Thank you, ----really.