06A 103 221 BH : Breather hose cylinder head cover / intake for Golf 4

This breather hose ensures the connection between the cylinder head cover and the intake system on the Volkswagen Golf 4 and Volkswagen Bora equipped with the 1.8 Turbo engine in 150 bhp versions (engine code AUM) and 180 bhp (engine code AUQ). It is part of the crankcase ventilation circuit and allows the evacuation of crankcase gases towards the intake, contributing to the proper functioning of the engine and the limitation of emissions. Its replacement is necessary during a restoration or thorough maintenance, particularly when the original hose shows cracks, excessive rigidity or leaks. As a new replacement part, it allows the operating conditions original to these iconic engines to be restored.