VW O-Ring - Genuine VW WHT004793A

Product Information

The engine crankcase vent valve, also referred to as the PCV (Positive Crankcase Ventilation) valve, is part of a vehicle’s emission control system. It helps manage the pressure inside the engine’s crankcase by allowing gases that build up in the crankcase to be vented back into the intake manifold. These gases are then burned in the combustion process, reducing harmful emissions. The PCV valve also prevents oil contamination and helps maintain proper engine performance by controlling the amount of blow-by gases (unburned fuel and air mixture) escaping from the combustion chamber.

• Rough Idle or Engine Misfire: A faulty or clogged PCV valve can cause the air-fuel mixture in the engine to become unbalanced, leading to rough idling or even engine misfires, especially when the car is idling.
• Oil Consumption: A faulty vent valve can cause pressure to build up inside the crankcase, which may push oil out through seals or gaskets, resulting in oil leaks. Excessive pressure can also force oil into the intake manifold, leading to increased oil consumption.
• Sludge Buildup: If the valve is stuck closed or blocked, the blow-by gases can’t escape the crankcase properly. This can cause condensation and oil to mix, forming sludge inside the engine. This sludge can block oil passages, leading to lubrication issues and engine damage over time.

About Genuine VW Audi

The Volkswagen Group, also known as “VAG”, consists of Volkswagen, Audi, Lamborghini, Bentley, Bugatti, Porsche, Ducati, MAN, Scania, SEAT, and Skoda. The original parts used by VAG to build your car are available as replacement parts under the “Genuine VAG” brand. Manufactured under the direction of VAG, expect excellent quality and a premium price since these parts are available exclusively through the VAG Dealership network.

You may not realize this, but the parts that make up your VAG are not necessarily manufactured by VAG. No cause for concern, as VAG designs the part, hires a manufacturer, and ensures its quality to you. In fact, many of these manufacturers have been making parts for VAG for decades. In our industry these manufacturers are called OEM (Original Equipment Manufacturers), and these are often brands you recognize, including Lemforder, ZF, Sachs, Bosch, Valeo, Zimmermann, Siemens VDO, Corteco, and more. Don’t be surprised to open that Genuine VAG parts box and find an OEM branded part inside, simply with the addition of a VAG logo.

Be sure to keep an eye out for OE tags on our product pages to quickly identify parts coming direct from OE manufacturers. That extra bit of insight could save you some serious money while shopping! Refer to our OE Academy for further information regarding the OE/OEM tags throughout the site.