Engine Crankcase Vent Blow-By Hose Assembly ️

This hose assembly is a key part of the engine breathing/ventilation system. It is needed to route oily crankcase vapors (blow-by gases) safely from the crankcase area to the intake path, where they can be re-burned instead of leaking into the engine bay. By keeping pressure under control, it helps protect seals, gaskets, and keeps the engine running clean and stable.

How It Works ⚙️

During combustion, a small amount of gas slips past piston rings and builds pressure in the crankcase. This hose carries those vapors through the ventilation circuit. Its molded shape keeps correct flow, avoids kinks, and handles heat, oil mist, and vibration. Proper sealing at both ends prevents vacuum leaks and keeps the fuel/air mixture in balance.

Signs of Failure & What Happens If It Breaks

A cracked, soft, or split hose can cause vacuum leaks, oily smell, whistling noises, rough idle, lean running, and higher oil consumption. In worse cases, crankcase pressure rises and may push oil past seals, leading to leaks, smoking, dirty throttle/intake parts, and possible check engine light. Replacing it restores correct ventilation and helps extend engine life.

Compatible Models ✅

• Navara
• Nv
• Patrol
• Pathfinder
• Xterra
• Frontier
• Nv3500