Audi AN Coolant Line Upgrade - C7 S6/S7
1. Remove OEM fittings (pull up on tab wire), then pull straight out.
2.Once OEM lines are removed, take apart the new fittings and push the new collar portion down on the tabs. and then thread the insert into the collar to lock the fitting into the tank.
4. Remove the oem lines from the radiator. THIS will make a mess from coolant and height so make sure to have a rag or something to collect dropping coolant.
5. The front Coolant line is the 45 degree and 90 Degree Line. Do not follow the OEM routing for this line. Route the line around the front of the motor and through the center of the core support to the radiator.
5. Line coming from the side of the bottle attaches to the coolant crossover line on the passenger side of the motor. Use the barb fitting and attach it to the rubber hose on the coolant crossover line. Easiest method we found was to remove the rubber hose entirely from the car and attach the barb/fitting on the rubber hose, and then rettach that to the crossover line.