Draining Audi A8 D2

Identifying Thermostat Installation Position. Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

1. Carefully open cap of expansion tank (to release pressure), then close it again.
2. Remove noise insulation panel. (Scheme 5): Removing Noise Insulation Panel
3. Remove left air grille in bumper.
4. Place drain pan VW 1306 (or equivalent) below vehicle.
5. Attach drain hose, approx. 12 mm (1/2 in.) inside diameter, to drain fitting at bottom left of radiator. (Scheme 6): Attaching Drain Hose To Drain Fitting At Bottom Left Of Radiator
6. Route other end of drain hose into drain pan. NOTE: Always drain coolant into a clean container.
7. Open coolant drain plug through air intake grille opening in left side of bumper. (Scheme 7): Opening Coolant Drain Plug Through Air Intake Grille Opening
8. Open drain plug at left of engine below knock sensor. (Scheme 8): Opening Drain Plug At Left Of Engine Below Knock Sensor
9. Open drain plug on oil cooler housing behind oil filter. (Scheme 9): Opening Drain Plug On Oil Cooler Housing Behind Oil Filter
10. At radiator, disconnect return line to expansion tank.
11. Hold pipe connection at radiator closed with finger.
12. Blow compressed air into detached return line until coolant no longer flows out of any of three drain openings.

Scheme 9

Scheme 10

Scheme 11

1. Close drain plugs located at left of engine block at oil cooler housing and at bottom left of radiator.
2. Re-connect return line at radiator.
3. Remove cap on expansion tank, attach adapter VAG 1274/1 and extend to 100 mm using 42 mm diameter (1-5/8 in.) hose. (Scheme 10): Attaching Adapter VAG 1274/1 To Coolant Expansion Tank
4. Open vent screws at feed and return lines of heating system. (Scheme 11): Locating Vent Screws Of Coolant Hoses At Heater Core
5. Add coolant until it flows from vent valves.
6. Close vent valves.
7. Re-install cover of expansion tank.
8. Disconnect 2-pin harness connector from pump unit. see scheme 12: Disconnecting 2-Pin Harness Connector From Pump Unit
9. Set heating/air conditioning controls to "LO."
10. Start and run engine at approx. 2000 RPM, for approx. 3 minutes.
11. Check fluid level in expansion tank and refill if necessary to max. level. WARNING: The cooling system is pressurized when the engine is warm. When opening the expansion tank, wear gloves and other appropriate protection, cover the cap with a cloth, and open carefully to relieve system pressure slowly.
12. Re-connect 2-pin harness connector to pump.
13. Set heating/air conditioning controls to "HI" and blower speed to lowest setting.
14. Start and run engine at 2000-3000 RPM for about 10 minutes.
15. Stop engine (switch ignition off).
16. Switch ignition back on.

Note. When the heating and air conditioning controls are set to "HI," the electric pump to the heater must not make any noise. Noise indicates that air is trapped in the heating system and requires the bleeding/venting process to be repeated.

If there are no unusual noises

1. Switch ignition off.
2. Check expansion tank fluid level and refill if necessary.