034Motorsport Billet PCV Check Valve for Audi A4, TT, RS6 and VW Beetle, Golf, Jetta, Passat (1997–2005)

The 034Motorsport 034-101-2002 is a billet aluminum PCV check valve that replaces the factory plastic crankcase ventilation check valve on 1997–2005 Audi A4, TT, and RS6 models and Volkswagen Beetle, Golf, Jetta, and Passat models. Its housing is CNC-machined from billet aluminum. Inside are a stainless steel ball bearing and spring, so it works as a spring-loaded ball-style valve. It takes the place of factory part number 035 103 245 A, a plastic valve with a reputation for trouble. 034Motorsport developed it as a simple bolt-on piece for turbocharged engines, including the 1.8T. The valve is made in the United States.

034Motorsport parts sold by PMB carry a 24-month warranty.

A positive crankcase ventilation system routes blow-by gases from the crankcase back into the intake manifold, where they are burned instead of vented. The check valve lets gases flow one way and keeps boost pressure from pushing back into the crankcase side. The two ends of this valve are different sizes. The pressure side has a 1/2 inch nipple and the vacuum side has a 1 inch outside diameter. 034Motorsport rates the valve for applications up to 100 PSI or more. Because the valve only blocks flow in one direction, it can also be used in other setups where pressure has to be kept out of a specific hose or chamber.

Technical Details

• Manufacturer: 034Motorsport
• Part number: 034-101-2002
• Part type: PCV check valve, spring-loaded ball style
• Housing: CNC-machined billet aluminum
• Internals: stainless steel ball bearing and spring
• Connections: 1/2 inch nipple on the pressure side, 1 inch OD on the vacuum side
• Pressure rating: up to 100 PSI or more
• Replaces factory plastic valve 035 103 245 A
• Made in the United States
• Warranty: 24 months

Installation & Tuning Notes

The valve installs as a direct bolt-on in place of the factory plastic unit. Before you connect the hoses, match the 1/2 inch nipple to the pressure side and the 1 inch end to the vacuum side. A valve installed backward will block flow in the direction the system needs.

Common Questions

What happens when a PCV valve fails?
A clogged or faulty valve can cause a rough idle or misfires. It can also build crankcase pressure that pushes oil past seals and gaskets or into the intake. A valve stuck closed traps blow-by gases, which can lead to sludge inside the engine.

Can this valve be used outside the factory PCV location?
Yes. 034Motorsport says it suits universal applications where pressure needs to be kept out of a specific hose or chamber, with 1/2 inch and 1 inch connections and a rating up to 100 PSI or more.

PMB sells 034Motorsport parts for owners who want a metal valve in place of the factory plastic one.

Fitment & Compatibility

Check the fitment table below for your model and year. Confirm your engine before ordering, since this valve replaces a specific factory PCV check valve. Send PMB your VIN and we will confirm fit.