Some additional troubleshooting techniques for tracing down a leaking head gasket or a cracked cylinder head or block: - Shut down the engine and let it sit all night. When engine is stone-cold the next day, pull the spark plugs. In a leaking cylinder, small water droplets can appear on the spark plug and inside the combustion chamber/cylinder. - When starting a cold engine, examine for signs of an engine misfire. A wet cylinder compromised with coolant can misfire when cold. - Motor oil will eventually emulsify (milky appearance) when coolant leaks into the cylinders and eventually down into the crankcase.
