The cylinder head is an important part of the engine that helps produce energy through combustion. A crack in the cylinder head can cause catastrophic engine failure while driving. The cylinder houses the piston that compresses fuel and air to produce energy through combustion. Common symptoms of cylinder head problems include foul odors, smoke from the exhaust, coolant leaks, engine misfires, and the engine running off-timing. Regular maintenance like keeping the radiator full can help prevent overheating issues that often lead to cylinder head cracks and failures.