This water pipe blanking plug, part number 4D0133335, is a precision moulded sealing component manufactured to original equipment specifications for Audi A6 Allroad Quattro models. Designed to cap off unused coolant or heater hose ports on the engine block, cylinder head, or auxiliary heater circuit, it effectively prevents coolant loss, air ingress, and system contamination. Constructed from high temperature resistant PA66 GF30 composite, this plug withstands continuous exposure to pressurised ethylene glycol based coolants, engine oil mist, and under bonnet temperatures up to 135°C. The external ribbed grip and integrated O ring sealing channel are engineered to exact OE dimensions, ensuring a snug, leak proof fit when installed with the recommended rubber seal.

This direct replacement part matches the factory interface perfectly, allowing for quick installation without any adaptors or thread modifications. Compatible with Audi A6 Allroad 4F and 4G generations equipped with 3.0 TDI, 3.2 FSI, and 4.2 V8 engines, as well as selected A8 and Q7 models sharing the same cooling architecture, it restores the integrity of the cooling system and eliminates persistent seepage issues commonly found at blanked ports. Symptoms of a degraded plug include crystallised coolant residue, gradual fluid loss, and intermittent heater performance; replacing with our unit resolves these problems and protects the water pump and thermostat from cavitation damage.

Every plug undergoes 100% leak testing at 2.0 bar air pressure, dimensional verification, and thermal shock cycling from 30°C to 140°C prior to packaging. The material meets OEM flammability V 0 and burst strength standards, ensuring long term durability even in harsh winter and summer conditions. Backed by a 24 month warranty against material or workmanship defects, this blanking plug offers a reliable, cost effective solution for workshops and individual owners alike. With its simple push fit design and proven sealing performance, it is the ideal choice for coolant system maintenance, engine swaps, or heater bypass modifications on your A6 Allroad.