How to Deal with a Malfunctioning Porsche Air-Oil Separator

Have you ever experienced a noticeable drop in your Porsche’s engine efficiency or noticed increased emissions? The answer might lie in the health of your Porsche Air-Oil Separator. The AOS is a device designed to handle the byproducts of combustion in an internal combustion engine, such as the one found in a Porsche. These byproducts include oil vapor, also known as blow-by gases, which can escape from the engine’s crankcase. If these gases are allowed to enter the engine’s intake system, they can lead to several issues.

Identifying and addressing issues with the Air-Oil Separator is crucial to maintaining the optimal performance and longevity of your Porsche vehicle.

How does the Air-Oil Separator (AOS) work?

The AOS is positioned in the engine’s ventilation system. As the engine operates, blow-by gases containing oil vapor are produced within the crankcase. These gases contain fine oil droplets and need to be properly managed. The blow-by gases are directed from the crankcase to the AOS. This is typically achieved through a series of hoses or tubing. Inside the AOS, the blow-by gases pass through a system of chambers, baffles, and membranes. These components are designed to separate the oil droplets from the air. This separation is crucial to prevent excessive oil from entering the engine’s intake system.

The separated oil is then returned to the engine’s oil pan through a drainage system. This ensures that the oil remains in the engine, where it’s needed for lubrication, and prevents it from being wasted or entering the exhaust system. After the oil has been separated and returned to the engine, the cleaned gas, now free of oil, is routed back to the engine’s intake system. This clean gas can be used for combustion without causing problems to your Porsche.

3 Signs of a Failing Air-Oil Separator

• Smoke from the exhaust: When the AOS is not functioning correctly, one of the most noticeable symptoms is the emission of dark smoke from the exhaust. This occurs because the faulty AOS allows excessive oil to enter the engine’s intake system. As a result, oil gets burned along with the fuel during the combustion process, leading to visible smoke. This smoke is usually higher during startup or acceleration.
• Oil leaks: A malfunctioning AOS can also result in oil accumulating in and around the AOS housing. This oil can eventually find its way out and cause visible oil leaks in the engine bay or on the ground beneath your Porsche.
• Check engine light: Modern Porsches are equipped with advanced onboard diagnostic systems that can detect issues with various engine components, including the AOS. When the AOS is malfunctioning, the car’s computer may trigger the check engine light to alert the driver to a problem that requires attention. A diagnostic scan by a qualified technician will provide more specific information about the issue.

How to Address AOS Issues

To address a malfunctioning AOS, the process begins with diagnosing the issue. You should first observe common symptoms, as mentioned. Further diagnostic insight can be gained by utilizing an OBD-II scanner to retrieve specific diagnostic trouble codes (DTCs). Next, conduct a thorough inspection of the AOS itself. During this inspection, look for visible signs of problems such as oil leakage, cracked hoses, or loose connections.

Should the AOS be identified as the source of the issue, it’s advisable to replace it rather than attempt repairs, as Porsche AOS units are not designed for this. To ensure the replacement process is carried out correctly, it’s recommended to consult a Porsche specialist who can carefully conduct the AOS replacement.

Let Us Revive Your Porsche with Our AOS Solutions

The key to preserving your vehicle’s top-notch performance is swift and accurate diagnosis and repair. At Bimmer Performance, we specialize in Porsche maintenance and repair, and we’ve gained a reputation as the go-to experts when it comes to addressing AOS issues. Our team is well-versed in the intricacies of Porsche engines, and we understand the importance of a well-functioning AOS.

Whether you’re in Sugar Land, Mission Bend, Cinco Ranch, Katy, or Houston, TX, our dedicated team is here to assist you. We’re committed to ensuring that your Porsche runs at its peak once again, delivering the exhilarating driving experience you expect from this iconic brand. Schedule an appointment with us today, and let us work our magic to restore your Porsche to its legendary performance standards.

* White Porsche 911 Turbo S Car image credit goes to: Brandon Woyshnis.