Engine Cooling - 3.0l 6-cylinder 5v, Avk Audi A4 B6

Cooling system components, removing and installing

Note. The cooling system is under pressure when engine is warm. If necessary reduce pressure before repair. Secure all hose connections using hose clamps appropriate for the model type. VAG1921 hose clip pliers are recommended for installing spring-type clamps. Always replace gaskets, seals and O -rings. The arrows which are marked on coolant lines and hoses must face each other.

Coolant hose connection diagram

Note. The following list refers to items in (Scheme 52).

1. Radiator Removing and installing, see «RADIATOR, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk) After replacing, replace coolant
2. Bleeder screw - 15 Nm
3. Coolant thermostat Removing and installing, see «COOLANT THERMOSTAT, REMOVING, INSTALLING AND CHECKING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk) Checking See «CHECK COOLANT REGULATOR»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk__check-coolant-regulator)
4. Cylinder head/Cylinder block After replacing, replace coolant
5. Throttle valve control module -J338
6. Bleeder hole at coolant hose to heater core
7. Heater core After replacing, replace coolant
8. Expansion tank with cap Pressure relief valve in cap, checking. See «PRESSURE RELIEF VALVE IN CAP, CHECKING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk__pressure-relief-valve-in-cap-checking) .
9. Oil cooler
10. Coolant pump Removing and installing, see «COOLANT PUMP, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk) Check for ease of movement

Scheme 52

Scheme 53

1. VAG1274/8
2. VAG1274/10 adapter for VAG1274 tester
3. VAG1306 drip tray for VAG1202A
4. VAG1921 hose clip pliers
5. T10007 refractometer

Draining

Note. Drained coolant must be stored in a clean container for disposal or reuse.

Scheme 54

Scheme 55

1. Open cap of coolant expansion tank.
2. For vehicles with auxiliary heater, remove bolts (arrows) for exhaust pipe of parking heater/auxiliary heater on noise insulation.
3. Remove bolts or quick-release screws -1- and -2- and remove front noise insulation.
4. Place VAG1306 Drip Tray beneath engine.

Vehicles with drain plug

Scheme 56

1. Turn radiator drain plug -2- counterclockwise, if needed attach accessory hose to connection flange and drain coolant.

Vehicles without drain plug

1. Remove retaining clamp for Engine Coolant Temperature (ECT) Sensor (on Radiator) -G83-.
2. Remove Engine Coolant Temperature (ECT) sensor from outlet and drain coolant.

All

Scheme 57

1. In addition, disconnect coolant hose at oil cooler (arrow) and drain remaining coolant.

Filling

Note. The cooling system must be filled year round with frost and corrosion protection additives. Only use coolant additive G 012 A8 D (according to TL VW 774 D). Characteristic: red color.

1. If the fluid in expansion tank is brown, G012 A8 D has been mixed with other coolant. In this case, flush cooling system and change coolant. To flush, fill cooling system with clear water and let engine run for approx. 2 minutes. Flushing system should remove most of old coolant .
2. G 012 A8 D and coolant additives are marked with "according to TL VW 774 D" prevent frost and corrosion damage as well as lime deposits. They also raise the boiling point. Therefore, cooling system must be filled year round with frost and corrosion protection additives .
3. A higher boiling point improves engine reliability under heavy load particularly in countries with tropical climates .
4. Frost protection must be ensured to about -25 ° C (about -35 ° C in countries with arctic climates) .
5. The coolant concentration must not be reduced by adding water even in warmer seasons and in warmer countries. The coolant additive portion must be at least 40% .
6. If for climatic reasons greater frost protection is required, the amount of G 012 A8 D can be increased, but only up to 60% (frost protection to about -40 ° C), otherwise frost protection and cooling effectiveness will be reduced again .
7. Use only clean drinking water for mixing with the coolant .
8. If the radiator, heater core, cylinder head or cylinder head gasket is replaced, completely replace the engine coolant .
9. For coolant G012 A8 D, use T10007 refractometer to test frost protection in cooling system .

Recommended mixture ratios

COOLANT MIXTURE RATIOS CHART

Vehicles with drain plug

Scheme 58

1. Unscrew drain plug -2- at radiator clockwise.

Vehicles without drain plug

1. Insert Engine Coolant Temperature (ECT) Sensor (on Radiator) -G83- with new O-ring into outlet and secure it with retaining clamps.

All

Scheme 59

1. Connect coolant hose to oil cooler (arrow).

Scheme 60

Scheme 61

Scheme 62

Scheme 63

Scheme 64

1. Screw VAG1274/8 Adapter onto expansion tank.
2. Attach VAG1274/10 Special Tool to VAG1274/1 Adapter.
3. Pull off rubber seal of plenum chamber cover in direction of (arrow).
4. Remove cover -1- toward front.
5. Remove front engine cover (arrows).
6. Remove bleeder screw (arrow).
7. Fill up coolant until it escapes from the coolant hose bleeder hole.
8. Tighten bleeder screw to 15 Nm. NOTE: Always replace sealing ring.
9. Loosen coolant hose to heater core and pull back hose sufficiently so that the bleeder hole (arrow) is no longer sealed by the connection.
10. Fill up coolant until it escapes from the coolant hose bleeder hole.
11. Slide coolant hose onto connection sleeve and secure using spring -type clamp.
12. Install coolant expansion tank cap.
13. Start engine and maintain an engine speed of about 2000 RPM for approx. 3 minutes.
14. Allow engine to idle until lower coolant hose at radiator is hot. WARNING: Cover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.
15. Check coolant level and top off if necessary. With engine at operating temperature, coolant level must be at max. marking, with engine cold, it must be between min. and max. marking.
16. Turn engine off.

Tightening torque

TIGHTENING TORQUE: COOLANT PIPE BLEEDER SCRES

Coolant pump and coolant regulator

Note. The following list refers to items in (Scheme 65).

1. 10 Nm
2. 10 Nm
3. Coolant pump Removing and installing, see «COOLANT PUMP, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk) Check for ease of movement
4. Gasket Always replace
5. O-ring Always replace
6. Coolant thermostat with connecting piece Can only be replaced together with the coolant regulator. Removing and installing, see «COOLANT THERMOSTAT, REMOVING, INSTALLING AND CHECKING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk) Checking, see «CHECK COOLANT REGULATOR»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk__check-coolant-regulator)
7. 10 Nm

Scheme 65

Scheme 66

Scheme 67

1. Drain coolant. See «COOLANT, DRAINING AND REFILLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk) .
2. Toothed (timing) belt, removing. See «TOOTHED BELT, REMOVING AND INSTALLING»(ref-197058-S27623366062005101100000) .
3. Remove camshaft gears from right cylinder head.
4. Unscrew bolts -1- and remove bracket with idler roller.
5. Unscrew bolts -2- and remove toothed belt guard at right rear.
6. Remove eccentric pulley for toothed belt.
7. Remove nuts -2- for toothed belt guard at left rear.
8. Remove bolts -1- for coolant pump and remove coolant pump.

Installing

Installation is reverse of removal, noting the following

Note. Replace gaskets and O-rings.

1. Install toothed belt (adjust timing). See «TOOTHED BELT, REMOVING AND INSTALLING»(ref-197058-S27623366062005101100000) .
2. Top off coolant. See «FILLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk__filling) .

Tightening torques

TIGHTENING TORQUE: COOLANT PUMP

Scheme 68

1. Drain coolant. See «COOLANT, DRAINING AND REFILLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk) .
2. Remove intake manifold. See «INTAKE MANIFOLD, REMOVING AND INSTALLING»(ref-197058-S00386977522005101100000) .
3. Remove bolts -1- and -2-.
4. Disconnect coolant hose (arrows).
5. Remove coolant regulator with connection.

Installation is reverse of removal, noting the following

Note. Replace O -ring.

1. Clean and/or smooth O-ring sealing surface before installing.
2. Install coolant regulator with coolant regulator housing.
3. Install intake manifold. See «INTAKE MANIFOLD, REMOVING AND INSTALLING»(ref-197058-S00386977522005101100000) .

TIGHTENING TORQUES: COOLANT REGULATOR (THERMOSTAT) HOUSING

Check coolant regulator

1. Warm thermostat in hot water bath. COOLANT REGULATOR SPECIFICATION Starts to open Opening end Opens approx. 87°C approx. 102°C (1) min. 8 mm (1) Cannot test this.

Coolant lines, overview

Note. The following list refers to items in (Scheme 69).

1. 10 Nm
2. Front coolant pipe Removing and installing, see «FRONT COOLANT LINE, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk)
3. 22 Nm
4. O-Rings Always replace
5. Coolant pipe, right Removing and installing, see «RIGHT COOLANT LINE, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk)
6. 10 Nm
7. O-ring Always replace
8. 10 Nm
9. O-ring Always replace
10. Engine Coolant Temperature (ECT) Sensor -G2-/-G62
11. Retaining clip
12. Coolant hose to heater core
13. Coolant hose to expansion tank
14. Connecting piece Tighten to 15 Nm
15. Seal Always replace
16. Coolant hose to heater core
17. 10 Nm
18. Rear coolant pipe Removing and installing, see «REAR COOLANT LINE, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk)
19. O-Rings Always replace
20. Coolant hose To top of radiator
21. Coolant hose To oil cooler

Scheme 69

Scheme 70

1. 3094 hose clamps
2. Oil receptacle

Removing

Note. All cable ties opened or cut during engine removal must be reinstalled at the same locations during installation.

Scheme 71

Scheme 72

Scheme 73

1. Remove intake manifold. See «INTAKE MANIFOLD, REMOVING AND INSTALLING»(ref-197058-S00386977522005101100000) .
2. Toothed belt, removing. See «TOOTHED BELT, REMOVING AND INSTALLING»(ref-197058-S27623366062005101100000) .
3. Remove camshaft gears from left cylinder head.
4. Unscrew bolts -1- and -2- and remove toothed belt guard ar rear left.
5. Place oil pan underneath.
6. Clamp off two hoses at hydraulic fluid supply line using 3094 hose clamps.
7. Disconnect both hydraulic hoses from supply line.
8. Disconnect coolant hoses at front coolant pipe.
9. Remove bolts -1- and -2- and move lines at coolant pipe to side.
10. Remove coolant pipe toward front (arrow).

Installation is reverse of removal, noting the following

Note. Secure all hose connections using hose clamps appropriate for the model type. Replace O -rings.

1. Clean and/or smooth O-ring sealing surface before installing.
2. Coat new O-ring with G12 and slide onto coolant pipe.
3. Slide front coolant pipe into the hole at rear coolant pipe.
4. Install intake manifold. See «INTAKE MANIFOLD, REMOVING AND INSTALLING»(ref-197058-S00386977522005101100000) .
5. Install toothed belt (adjust timing). See «TOOTHED BELT, REMOVING AND INSTALLING»(ref-197058-S27623366062005101100000) .
6. Fill up power steering fluid and bleed steering system. See «POWER STEERING SYSTEM, BLEEDING»(/audi/a4/b6-2000-2006/remont/steering-column-switches/#steering) .

TIGHTENING TORQUES: FRONT COOLANT PIPE

Scheme 74

1. Remove intake manifold. See «INTAKE MANIFOLD, REMOVING AND INSTALLING»(ref-197058-S00386977522005101100000) .
2. Disconnect rear coolant hose -2- from right coolant pipe.
3. Remove bolts -1-.
4. Pull right coolant pipe out of cylinder block toward rear (arrow).

Installation is reverse of removal, noting the following

Note. Secure all hose connections using hose clamps appropriate for the model type. Replace O-rings.

1. Clean and/or smooth O-ring sealing surface before installing.
2. Coat new O-ring with G12 and slide onto coolant pipe.
3. Slide coolant pipe into the hole at cylinder block.
4. Install intake manifold. See «INTAKE MANIFOLD, REMOVING AND INSTALLING»(ref-197058-S00386977522005101100000) .

TIGHTENING TORQUE: RIGHT COOLANT PIPE

Note. All cable ties opened or cut during engine removal must be reinstalled at the same locations during installation.

Scheme 75

1. Remove right coolant pipe. See «RIGHT COOLANT LINE, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk) .
2. Expose wires at hose of crankshaft housing ventilation.
3. Remove hose of crankshaft housing ventilation (arrow).

Scheme 76

1. Disconnect vacuum hose to brake booster (arrows).

Scheme 77

Scheme 78

Scheme 79

1. Remove heat shield for harness connectors at left of bulkhead, if installed.
2. Remove coolant hose -4-. (Scheme 77)
3. Remove bolts -2- and nut -5- and remove hose for secondary air injection.
4. Disconnect vacuum hose -3- from combination valve. (Scheme 77)
5. Remove bolts -1- and remove combination valve for secondary air injection.
6. Remove coolant hose -6-. NOTE: Illustration is shown with engine removed.
7. Disconnect electrical harness connector -2- at Engine Coolant Temperature (ECT) Sensor -G2-/-G62-. (Scheme 78)
8. Disconnect hydraulic line of power steering at rear coolant pipe -1-.
9. Remove screw clips for electrical wiring harness at rear coolant pipe.
10. Expose electrical wires at rear coolant pipe.
11. Remove bolts -1- and -2-.
12. Remove coolant pipes toward rear.

Installation is reverse of removal, noting the following

Note. Secure all hose connections using hose clamps appropriate for the model type. Replace seals and O-rings.

1. Clean and/or smooth O-rings sealing surface before installing.
2. Coat new O-rings with G12 and slide onto coolant pipe.
3. Install right coolant pipe. See «RIGHT COOLANT LINE, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk) .

TIGHTENING TORQUES: REAR COOLANT PIPES

Scheme 80

1. VAG1306 drip tray for VAG1202A

Scheme 81

Scheme 82

1. Remove front bumper: See «FRONT BUMPER»(/audi/a4/b6-2000-2006/remont/exterior-body-panels/#bumpers-except-cabriolet) (except Cabriolet), or «FRONT BUMPER»(/audi/a4/b6-2000-2006/remont/exterior-body-panels/#bumpers-cabriolet) (Cabriolet). NOTE: Drained coolant must be stored in a clean container for disposal or reuse. WARNING: Cover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.
2. Open cap of coolant expansion tank.
3. For vehicles with auxiliary heater, remove bolts (arrows) for exhaust pipe of parking heater/auxiliary heater on noise insulation.
4. Remove bolts or quick-release screws -1- and -2- and remove front noise insulation.
5. Place VAG1306 Drip Tray beneath engine.

Scheme 83

1. Turn radiator drain plug -2- counterclockwise, if needed attach accessory hose to connection flange and drain coolant.

Vehicles without drain plug

1. Remove retaining clamp for Engine Coolant Temperature (ECT) Sensor (on Radiator) -G83-.
2. Remove Engine Coolant Temperature (ECT) sensor from outlet and drain coolant.

Scheme 84

Scheme 85

1. Pull off retaining clip -1- for lower coolant hose and disconnect coolant hose from radiator.
2. Disconnect left coolant hose from radiator (arrow).
3. Remove cover -1- in engine compartment (left side).
4. Disconnect top coolant hose (arrow) from radiator.

Scheme 86

Scheme 87

1. Remove cover -1- in engine compartment (right side).
2. Remove bolts (arrows). (Scheme 88)
3. Detach Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80- -1- at air guide.
4. Remove air guide -2-.

Note. Observe the rules of cleanliness for working on automatic transmissions:.

See RULES FOR CLEANLINESS .

See

Scheme 88

1. Place an oil receptacle underneath.
2. Disconnect top (arrow) and bottom ATF lines from radiator: See .
3. Tie up ATF lines to top of longmember to prevent fluid from escaping.

Scheme 89

Scheme 90

Scheme 91

1. Remove air guides from left and right of radiator (arrows).
2. Unclip temperature sensor -2- for outside temperature display from bracket. (Scheme 91)
3. Remove bolts -3- and -4- and remove power steering cooling coil, hoses remain connected.
4. Disconnect harness connector -1- at High Pressure Sensor -G65-. WARNING: Do not open refrigerant circuit for A/C system.
5. Remove condenser mounting bolts (arrows). NOTE: Do not bend or stretch lines or hoses as condenser and/or refrigerant lines/hoses may be damaged.
6. Carefully swing condenser downward and move aside.
7. Loosen both radiator retaining bolts, pull up and remove (arrows).
8. Tilt radiator forward, pull up and remove.

Installation is reverse of removal, noting the following

1. Install front bumper. See «FRONT BUMPER»(/audi/a4/b6-2000-2006/remont/exterior-body-panels/#bumpers-except-cabriolet) (except Cabriolet), or «FRONT BUMPER»(/audi/a4/b6-2000-2006/remont/exterior-body-panels/#bumpers-cabriolet) (Cabriolet).
2. Top off coolant. See «FILLING»(/audi/a4/b6-2000-2006/remont/cooling-fan/#engine-cooling-30l-6-cylinder-5v-avk__filling) .

Note. Complete coolant must be replaced if the radiator was replaced.

Vehicles with automatic transmission

1. Secure ATF lines
2. Check ATF level. See «CHECKING FLUID LEVELS»(/audi/a4/b6-2000-2006/remont/automatic-trans/#automatic-transmission-servicing-at-01j-multitronic-cvt__checking-fluid-levels) (01J auto. trans.), or «CHECKING FLUID LEVELS»(/audi/a4/b6-2000-2006/remont/automatic-trans/#servicing-at-01v-with-18l-30l__checking-fluid-levels) (01V auto. trans.).

TIGHTENING TORQUE: CONDENSER

Scheme 92

1. VAS1978 wiring harness repair kit

Procedure

Note. Coolant FC (Fan Control) Control Module and coolant fan motor are supplied as a replacement part without harness connector. Repairs to wiring harnesses and connectors must only be performed using the VAS1978 wiring harness repair kit.

Detailed instructions on how to use VAS1978 are supplied with the repair kit.

The manual also explains how to repair open circuits and faulty connectors.

Scheme 93

Scheme 94

1. VAG1274 cooling system tester
2. VAG1274/8
3. VAG1274/9 Adapter

Test requirement

1. Engine at operating temperature.

Test sequence

Scheme 95

1. Open cap of coolant expansion tank.
2. Attach VAG1274 Cooling System Tester together with VAG1274/8 adapter to coolant expansion tank.
3. Use tester hand pump to create a pressure of approx. 1.0 bar.
4. If pressure drops, detect leak and repair malfunction.

Pressure relief valve in cap, checking

1. Using VAG1274/9 Adapter attach VAG1274 Cooling System Tester to coolant reservoir tank cap.
2. Pump using hand pump. Pressure release valve must open at a positive pressure of 1.4 to 1.6 bar.

Scheme 96

See also:
• POWER STEERING SYSTEM, BLEEDING
• FRONT BUMPER
• FRONT BUMPER
• RULES FOR CLEANLINESS
• CHECKING FLUID LEVELS
• CHECKING FLUID LEVELS
• RADIATOR, REMOVING AND INSTALLING
• CHECK COOLANT REGULATOR
• PRESSURE RELIEF VALVE IN CAP, CHECKING
• FILLING