Walbro 525 Fuel pump kit w/ filter and 4x Viton O-Rings for fitting to stock B5 S4 or any B6/C5 fuel basket.

Will fit an A4 if you source an S4 basket or purchase a 39mm Fuel Pump adapter and remove the supplied o rings from the pump.

Absolutely must run our fuel pump relay kit if this is installed in a B5. 

B5 requires the suction jet pump to be unplugged from under the fuel lid and a hose added to direct return fuel to the basket.  This may cause low fuel level starvation issues in an avant due to tank design.

B6 requires the suction jet to be drilled out more or a secondary smaller return line added that is large enough to reduce idle fuel pressure to normal but small enough to retain some backpressure to allow the suction jet to still perform and not cause low level fuel starvation issues.