Description
Your engine relies on air being present in the combustion chamber in order to create the perfect ratio of air and fuel to burn for the engine to run. In order to allow this air into the combustion chamber while still allowing the combustion chamber to be sealed during combustion, valves are used.
Intake valves are opened and closed from the mechanical action of the camshaft and associated valvetrain components. Even though valves will last quite a long time, they can still fail, and when they do they will cause rough running conditions as well as poor emissions.
Some of the factors that can influence valve life are proper maintenance, especially oil changes as well as using the proper grade of fuel. Some of the things that can affect valve life that you cannot control are timing issues. If your timing chain breaks, or your timing chain tensioner fails, the valve can come into contact with the pistons which will bend them.