What issue can arise when a fuel metering system operates under incorrect pressure conditions?

When a fuel metering system operates under incorrect pressure conditions, engine knocking can occur. This phenomenon is primarily caused by an improper air-fuel mixture that can lead to incomplete combustion within the engine cylinders. When the pressure is either too high or too low, it can disrupt the delicate balance required for optimal engine performance.

High pressure may result in an excessively rich mixture, meaning too much fuel is present compared to air. This can lead to premature ignition of the air-fuel mixture in the cylinder, causing knocking, which is the sound of abnormal combustion. Conversely, if the pressure is too low, it can produce a lean mixture, resulting in higher combustion temperatures that can cause engine knocking as well.

Understanding the relationship between fuel pressure and its impact on combustion is crucial for diagnosing and maintaining engine performance. Correct pressure ensures that the fuel metering system delivers the right amount of fuel, enabling efficient combustion and preventing potential damage to engine components due to knocking.