PCV Breather Hose

The 034Motorsport PCV Breather Hose offers a critical safety and reliability upgrade for EA839 2.9T and 3.0T V6 engines. It directly replaces the factory corrugated plastic breather hose, which is prone to failure and can lead to dangerous crankcase pressurization. This issue can force oil out of seals and the oil cap, potentially causing engine damage or even fire, as documented by an Audi TSB and illustrated in 034Motorsport's "Ashes to Asphalt" video. Engineered for enhanced durability, this PCV breather hose features proprietary check valves designed to offer restrictionless flow when open and a strong seal when closed, capable of holding over 40 PSI. The check valves use a durable synthetic rubber diaphragm and a nylon ball check valve for high heat and chemical resistance, suitable for both stock and Stage 3 tuned vehicles. The hose itself is constructed from 4-ply, reinforced, fluorolined silicone, designed to prevent collapse under vacuum or boost pressure and to resist oil vapor sweating. Installation is described as mild and straightforward, typically taking around one hour. The design retains the factory engine cover, ensuring a clean aesthetic. It is sold for racing use or for vehicles not registered for highway use, and is not legal for street use. The 034Motorsport PCV Breather Hose is suitable for a wide range of EA839-equipped Audi models, including the B9/B9.5 S4, S5, SQ5, and C8 A6 and A7, from 2018 to the present. It is designed to function flawlessly across all power levels, from bone-stock configurations to Stage 1, 2, and 3 Dynamic+ tuning suites.