Intake valves are essential components in internal combustion engines, allowing air and fuel to enter the combustion chamber. They open and close at precise times during the engine's cycle, ensuring optimal performance and efficiency. When the engine is in the intake stroke, the intake valve opens, creating a pathway for the air-fuel mixture to flow in. These valves are typically made of durable materials to withstand high temperatures and pressures. Proper functioning of the intake valves is crucial for engine performance, as any malfunction can lead to reduced power and increased emissions. Regular maintenance helps ensure they operate effectively throughout the engine's lifespan.