What are the symptoms of a faulty exhaust valve in the Volkswagen Passat?

[JacksonLynn]

The symptoms of a faulty exhaust valve in the Volkswagen Passat are the EGR being stuck in a closed state, which affects the vehicle's emissions, meaning emissions may not meet standards. If the EGR is stuck in an open state, the vehicle may exhibit black smoke emissions, lack of acceleration power, and increased fuel consumption. Introduction to the Exhaust Valve: The exhaust valve, also known as an oil separator or pressure control valve, is installed between the compressor outlet and the condenser inlet. Through separation, it improves heat transfer efficiency in the condenser and evaporator. Working Principle of the Exhaust Valve: High-pressure gas (consisting of gaseous refrigerant and lubricating oil) from the compressor enters the exhaust valve and flows through the guide vanes in a spiral motion. Centrifugal force and gravity separate the lubricating oil from the refrigerant gas, causing the oil to flow along the inner wall of the cylinder. The refrigerant gas is discharged from the exhaust valve through a central pipe with multiple baffles. The separated lubricating oil accumulates at the bottom of the oil separator and can be periodically drained or automatically returned to the compressor's crankcase via a float valve.