ALL VW OR AUDI CARS

they used to fit a bleed valve to the topmost heater hose,it aint got one now as you can simply undo the clip and vent it.(its either one of the two on top of the firewall).

worth trying the topmost heater hose for an airlock,just undo the clip and fill with antifreeze.then with the radcap off, run the engine until hot.to check water flow.....

try undoing the topmost hose for the heater to vent any trapped air.

the easiest way is to connect a hose to a top hose (the same diameter)and remove the radiator cap,this backward flush will get all the rust/dust from out of the system.then undo the clip on the bottom hose of the radiator to drain it before filling with the CORRECT antifreeze.then run the engine to full temp and undo the topmost heater hose to bleed any trapped air.i recommend 50/50 antifreeze to water.there are other ways but this works for me...