Normally your mechanic would perform a pressure test to see where the leak is, but when it's this small, it is more effective to add a small bottle of dark purple dye, then search a couple of days later with a black light. The dye will show up as a bright yellow stain that you can follow back to the source. Be sure to check at the inside of the tail pipe. Dye there indicates a leaking cylinder head gasket.
Saturday, November 9th, 2013 AT 12:56 AM