Engine Crankcase Ventilation Blow-By Hose Assembly ?️

This hose assembly is a key link in the engine’s crankcase ventilation system. It is needed to carry oily vapor and blow-by gases from the engine breathing circuit to the intake path, so pressure stays stable and seals stay protected.

How It Works

During normal driving, a small amount of combustion gas slips past piston rings. This hose routes those gases safely, helping the PCV flow stay smooth and preventing vapor from lingering inside the crankcase. Its molded shape keeps correct routing and prevents kinks, while tight connections reduce air leaks.

Symptoms If It’s Damaged

A cracked or soft hose can leak vacuum, pull unmetered air, and create oil mist around the engine bay ?. You may notice rough idle, whistling noises, oil seepage, increased oil consumption, or warning lights. Ignoring it can raise crankcase pressure and contribute to gasket leaks and poor running.

Compatible Models

• Infiniti QX70
• Infiniti FX