What Happens When the Engine Exhaust One-Way Valve Fails?

1 Answers
Nigel
07/29/25 3:29pm
When the exhaust valve is damaged, it cannot control the amount of exhaust gas recirculation. Excessive exhaust gas participating in recirculation will affect the ignition and performance of the air-fuel mixture, thereby impacting the engine's power output. This is particularly noticeable during engine idling, low-speed operation, light load conditions, and when the engine is cold, where the recirculated exhaust gas significantly affects engine performance. The function of the car exhaust valve: It allows a portion of the exhaust gas to re-enter the cylinder for combustion. This small amount of exhaust gas reduces the temperature inside the cylinder during combustion. Since NOX is generated under high-temperature and oxygen-rich conditions, this process inhibits NOX formation, thereby reducing NOX emissions. Causes of exhaust valve failure: 1. Quality issues with the exhaust valve itself. 2. Improper maintenance. 3. Fuel quality problems. 4. Aging. The exhaust valve operates under high engine temperatures and, like the valve cover gasket and rubber seals, is prone to aging.
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