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Engine Cooling System - 3.2l v6 4v - Bhe Audi TT 8N рестайлинг

Cooling System (mechanical) 93 illustrations ~3459 words

Cooling system components, removing and installing

WARNINGCover cap of expansion tank with rag and open carefully, as hot coolant may escape when opening.

Note. The cooling system is under pressure when the engine is warm. If necessary reduce pressure before repair. Secure all hose connections using hose clamps appropriate for the model type: see Parts catalog VAG 1921 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 1).

  1. Radiator Removing and Installing, see «RADIATOR, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) After replacing, fill with new coolant
  2. Non-return valve
  3. After-run coolant pump -V51- Removing and Installing, see «AFTER-RUN COOLANT PUMP -V51-, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe)
  4. Oil cooler After replacing, fill with new coolant
  5. Coolant pump See «COOLANT PUMP, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .
  6. Cylinder head/cylinder block After replacing, fill with new coolant
  7. Expansion tank
  8. Filler cap for expansion tank With pressure relief valve See «CHECKING PRESSURE RELIEF VALVE»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .
  9. Throttle valve control module -J338
  10. Heat exchanger After replacing, fill with new coolant
  11. Thermostat Removing and installing, see «THERMOSTAT HOUSING, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) Checking, see «THERMOSTAT HOUSING, CHECKING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe__thermostat-housing-checking)
  12. Non-return valve
  13. ATF cooler After replacing, fill with new coolant
  14. Auxiliary radiator After replacing, fill with new coolant

Scheme 1

Scheme 1
Scheme 1

Special tools and equipment required

  1. Adapter for cooling system tester V.A.G 1274/8
  2. Drip tray V.A.G 1306
  3. Hose clamp pliers V.A.G 1921
  4. Cooling system charge unit VAS 6096 with VAS 6096/1
  5. Refractometer T10007

Scheme 2

Scheme 2
Scheme 2

Draining

Note. Collect drained coolant in a clean container for re-use or disposal.

CAUTIONCover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.

Scheme 3

Scheme 3
Scheme 3

Scheme 4

Scheme 4
Scheme 4
  1. Open filler cap on expansion tank.
  2. Remove fasteners -1...3- and remove center sound insulation.
  3. Place drip tray V.A.G 1306 under engine.
  4. Turn drain plug (arrow) on radiator counter-clockwise and, if necessary, fit a drain hose to connection.
  5. In addition, remove lower coolant hose at After-run coolant pump -V51- (arrow) and drain remaining coolant.

Scheme 5

Scheme 5
Scheme 5

Filling

  1. The cooling system must be filled year round with a mixture of water and frost and corrosion protection additives.
  2. ONLY use coolant additive Plus G 012 A8F A1 (also designated as "G12+") meeting specification TL VW 774 F. Other coolant additives could seriously impair in particular the anticorrosion properties. The resulting damage could lead to loss of coolant and consequently to serious engine damage.
  3. Coolant additive "G12+" may be mixed with aditives "G11" and "G12".
  4. "G12+" and coolant additives marked with "Meets specification TL VW 774 F" prevent frost and corrosion damage as well as stop scale from forming. They also raise the boiling point. Therefore, cooling system must be filled year round with the correct antifreeze and corrosion protection additives.
  5. A higher boiling point improves engine reliability under heavy load particularly in countries with tropical climates.
  6. Frost protection must be ensured to about -25 ° C (about -35 ° C in countries with arctic climates).
  7. 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%.
  8. If greater frost protection is required in very cold climates, the amount of "G12+" can be increased, but only up to 60% (this gives frost protection to about -40° C). If the antifreeze percentage exceeds 60%, frost protection decreases again and cooling efficiency is also impaired.
  9. Only use clean drinking water for mixing coolant.
  10. If the radiator, heat exchanger, cylinder head, cylinder head gasket or cylinder block have been replaced, do not re-use the old coolant.
  11. Contaminated or dirty coolant must not be used again.
  12. To check frost protection level of coolant additive "G12+" use refractometer T10007.

Scheme 6

Scheme 6
Scheme 6

Scheme 7

Scheme 7
Scheme 7

Scheme 8

Scheme 8
Scheme 8

Scheme 9

Scheme 9
Scheme 9
  1. Close drain plug (arrow).
  2. Connect coolant hose to After-run coolant pump -V51- (arrow).
  3. Fill reservoir VAS 6096/1 with at least 8 liters of premixed coolant (based on recommended ratio): "G12+" (40%) and water (60%) for frost protection to 25 ° C "G12+" (50%) and water (50%) for frost protection to 35 ° C "G12+" (60%) and water (40%) for frost protection to 40 ° C
  4. Screw adapter for cooling system tester V.A.G 1274/8 onto coolant expansion tank.
  5. Mount cooling system charge unit VAS 6096 onto adapter V.A.G 1274/8.
  6. Feed vent hose -1- into a small container -2-. (The vented air draws along a small amount of coolant, which should be collected.)
  7. Close both valves -A- and -B- (turn lever perpendicular to direction of flow).
  8. Connect hose -3- to compressed air. Pressure: 6...10 bar
  9. Open valve -B- (turn lever in direction of flow).

The suction jet pump generates a vacuum in the cooling system.

  1. Needle on gauge must move into green zone

Scheme 10

Scheme 10
Scheme 10
  1. Also briefly open valve -A- (turn lever in direction of flow) so that hose on coolant expansion tank, VAS 6096/1, can fill with coolant.
  2. Close valve -A- again.
  3. Leave valve -B- open for another 2 minutes. Suction jet pump will continue generating a vacuum in the cooling system. Needle on gauge must remain in green zone.
  4. Close valve -B-. Needle on gauge must stop in green zone. Vacuum level in cooling system is then sufficient for subsequent filling.

If the needle does not reach the green area, repeat the process.

If the vacuum level drops, there is a leak in the cooling system.

  1. Disconnect compressed air hose.
  2. Open valve -A-.

The vacuum in the cooling system causes the coolant to be drawn out of the cooling system charge unit VAS 6096/1; the cooling system is then filled.

Scheme 11

Scheme 11
Scheme 11
  1. Check coolant level and top up coolant as far as MAX mark.
  2. Start engine, run for maximum of 2 minutes at approx. 1500 RPM and fill coolant up to overflow hole on expansion tank.
  3. Close expansion tank.
  4. Run engine until coolant fan starts. WARNING: Cover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.
  5. Check coolant level and top up if necessary. When engine is at normal operating temperature, coolant level must be at MAX mark. When engine is cold coolant level must be between MIN and MAX marks.
  6. Switch engine off.
  1. Support bracket 10-222 A
  2. Shackle 10-222 A/12
  3. Drip tray V.A.G 1306
  4. Coolant pump spanner V.A.G 1590
  5. Hose clamp pliers V.A.G 1921
  6. Bolt M8 x 40

Scheme 12

Scheme 12
Scheme 12

Removing

WARNINGCover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.

Scheme 13

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Scheme 26
Scheme 26
  1. Open filler cap on coolant expansion tank.
  2. Loosen hose clamp -1- and disconnect air hose at Throttle valve control module -J338-.
  3. Move electrical wire (arrow) clear. NOTE: Hose clamp -2- remains attached.
  4. To remove fasteners -1- at lock carrier, press pin -2- in approx. 4 mm (do not push in completely). Then pull fastener out upward.
  5. Remove covers (right side) -1- and -2- at lock carrier and above coolant expansion tank (arrows). NOTE: Before removing, mark direction of rotation of poly V-belt with chalk or a felt-tipped pen. If the belt runs in the opposite direction when it is re-installed, breakage may result.
  6. To release tension of poly V-belt, screw an M8 x 40 bolt into bore on tensioning element.
  7. Attach shackle 10-222 A/12 to right rear engine lifting eye.
  8. Place support bracket 10-222 A on surface of panel flange; spindle faces forward.
  9. Attach spindle hook to shackle.
  10. Pretension spindle slightly.
  11. Remove securing bolt (arrow) for power steering reservoir.
  12. Loosen bolts (arrows) of assembly mounting (left side) on engine.
  13. Remove fasteners -1...3- and remove center sound insulation.
  14. Remove right sound insulation (arrows).
  15. Place drip tray V.A.G 1306 under engine.
  16. Turn drain plug (arrow) on radiator counter-clockwise and, if necessary, install drain hose to connection.
  17. In addition, remove lower coolant hose at After-run coolant pump -V51- (arrow) and drain remaining coolant.
  18. Remove bolts (arrows -A-) for pendulum support at subframe.
  19. Remove pulley; counterhold using coolant pump spanner V.A.G 1590. NOTE: The pulley must not be removed if the engine has been taken out. In this case, the securing bolts for the coolant pump are accessible through the holes of the pulley.
  20. Remove bolts -1- for coolant pump -2-.
  21. Lower engine via spindle approx. 65 mm.
  22. Swing coolant pump forward and remove.

Installing

Installation is performed in the reverse order. Note the following

Note. Replace the O-ring.

Scheme 27

Scheme 27: Installing
Scheme 27: Installing
  1. Clean and smooth surface for O-ring as required.
  2. Moisten new O-ring with coolant "G12+".
  3. Install coolant pump -2-.
  4. Tighten bolts -1- for coolant pump.
  5. Install coolant pump pulley.
  6. Install poly V-belt. See «POLY V-BELT, REMOVING AND INSTALLING»(ref-200989-S10536469982005102400000) .
  7. Adjust engine mountings. See «ENGINE MOUNTINGS, ADJUSTING»(ref-200989-S27991014252005102400000) .

Tightening torques

ComponentNm
Coolant pump to cylinder block8
Pulley to coolant pump20

TIGHTENING TORQUES: COOLANT PUMP

Thermostat housing, component overview

Note. The following list refers to items in (Scheme 29).

  1. O-ring Replace
  2. Retaining clip
  3. Thermostat housing Removing and installing, see «THERMOSTAT HOUSING, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe)
  4. Bracket
  5. 10 Nm
  6. Thermostat Removing and Installing, see «THERMOSTAT HOUSING, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) Checking, see «THERMOSTAT HOUSING, CHECKING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe__thermostat-housing-checking)
  7. Connection
  8. Gasket Replace
  9. Engine Coolant Temperature (ECT) sensor -G62- With ECT sensor -G2- Dissipate cooling system pressure before removal if necessary
  10. Sealing plug Dissipate cooling system pressure before removal if necesary

Scheme 28

Scheme 28
Scheme 28

Scheme 29

Scheme 29: Special tools and equipment required
Scheme 29: Special tools and equipment required
  1. Drip tray V.A.G 1306
  2. Hose clamp pliers V.A.G 1921

Scheme 30

Scheme 30
Scheme 30

Note. Collect drained coolant in a clean container for re-use or disposal.

CAUTIONObserve procedure for disconnecting the battery. See BATTERY DISCONNECT PRECAUTIONS .

Scheme 31

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Scheme 47

Scheme 47
Scheme 47
  1. With ignition switched off, disconnect Ground cable (arrow) at battery (in luggage compartment, under floor cover). WARNING: Cover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.
  2. Open filler cap on coolant expansion tank.
  3. Remove fasteners -1...3- and remove center sound insulation.
  4. Place drip tray V.A.G 1306 under engine.
  5. Turn drain plug (arrow) on radiator counter-clockwise. If necessary, install drain hose to connection.
  6. In addition, remove lower coolant hose at After-run coolant pump -V51- (arrow) and drain remaining coolant.
  7. To remove fasteners -1- at lock carrier, press pin -2- in approx. 4 mm (do not push in completely). Then pull fastener out upward.
  8. Remove covers (left side) -1- and -2- at lock carrier and above main fuse box (arrows).
  9. Disconnect air hose -2- at Throttle valve control module -J338-. (Scheme 38)
  10. Disconnect electrical connector for Mass Air Flow (MAF) sensor -G70-, item -3-. (Scheme 38)
  11. Remove bolts -1- and -4-. (Scheme 38)
  12. Move electrical wire clear.
  13. Take out air cleaner housing.
  14. Unclip protective cover -1- for electrical cables.
  15. Fold bracket for fuse box upward (arrows).
  16. Remove fuse box by releasing tabs (arrow). NOTE: The wires remain connected.
  17. Remove carrier (arrows).
  18. Disconnect vacuum hose (arrow) at actuator for intake manifold change-over. (Scheme 42)
  19. Remove bolts -1- and -2- and remove actuator from intake manifold.
  20. Disconnect electrical connector (arrow) at Engine Coolant Temperature (ECT) sensor -G62-.
  21. Disconnect secondary air hose at position marked with an arrow.
  22. Move air hose at bracket clear.
  23. Disconnect coolant hoses at connections indicated (arrows).
  24. Remove bolts (arrows).
  25. Swing bracket for secondary air hose forward.
  26. Remove bolt (arrow) on bracket for wiring harness. CAUTION: When removing the thermostat housing, push coolant pipe toward coolant pump with an assembly lever to prevent it from also being removed.
  27. Remove thermostat housing -2-. When doing so, press coolant pipe -1- toward coolant pump with an assembly lever.

Installation is performed in the reverse order of removal. Note the following.

Note. Replace the seals and gaskets.

  1. Connect battery. See «BATTERY DISCONNECT PRECAUTIONS»(/audi/tt/8n-2003-2006/remont/charging-system/#generators-regulators) .
  2. Fill cooling system. See «COOLING SYSTEM, DRAINING AND FILLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .
ComponentNm
Thermostat housing to engine10
Bracket for wiring harness to engine10
Carrier to longitudinal member10
Air cleaner housing to body10

TIGHTENING TORQUES: THERMOSTAT HOUSING

Thermostat housing, checking

Note. Collect drained coolant in a clean container for re-use or disposal.

Scheme 48

Scheme 48: Thermostat housing, checking
Scheme 48: Thermostat housing, checking

Scheme 49

Scheme 49
Scheme 49
  1. Remove thermostat housing. See «THERMOSTAT HOUSING, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .
  2. Remove bolts (arrows) and remove connection -1-.
  3. Remove O-ring -3- with thermostat -2- from thermostat housing -1-.
  4. Heat thermostat in container of water. THERMOSTAT OPENING TEMPERATURES Starts to open Fully open Opening travel approx. 80 ° C approx. 105 ° C (1) at least 7 mm (1) Cannot be tested.
  5. Install thermostat housing. See «THERMOSTAT HOUSING, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .
  6. Fill cooling system. See «COOLING SYSTEM, DRAINING AND FILLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .

Tightening torque

ComponentNm
Connection to thermostat housing10

TIGHTENING TORQUE: CONNECTION TO THERMOSTAT HOUSING

Note. Collect drained Coolant in a clean container for re-use or disposal.

  1. Remove thermostat housing. See «THERMOSTAT HOUSING, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .
  2. Remove bracket for ancillary units. See «BRACKET FOR ANCILLARY UNITS, REMOVING AND INSTALLING»(ref-200989-S34534669282005102400000) .
  3. Unclip bracket for wiring on right from coolant pipe.
  4. Remove wiring harness from retainer on left.
  5. Pull off coolant hose to oil cooler.
  6. Pull coolant pipe out of cylinder block.

Note. Always replace seals and gaskets.

Scheme 50

Scheme 50: Installing
Scheme 50: Installing
  1. Before installing, clean and smoothen sealing surfaces for O-ring.
  2. Lubricate new O-ring -1- with "G 12+" and push onto coolant pipe -2-.
  3. Slide coolant pipe into bore in cylinder block.
  4. Install bracket for ancillary units See «BRACKET FOR ANCILLARY UNITS, REMOVING AND INSTALLING»(ref-200989-S34534669282005102400000) .
  5. Install thermostat housing. See «THERMOSTAT HOUSING, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .
  6. Fill cooling system. See «COOLING SYSTEM, DRAINING AND FILLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .

Scheme 51

Scheme 51: Special tools and equipment required
Scheme 51: Special tools and equipment required

Scheme 52

Scheme 52
Scheme 52
  1. Drip tray V.A.G 1306
  2. Hose clip pliers V.A.G 1921
WARNINGCover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.

Scheme 53

Scheme 53
Scheme 53

Scheme 54

Scheme 54
Scheme 54

Scheme 55

Scheme 55
Scheme 55
  1. Open filler cap on coolant expansion tank.
  2. Remove fasteners -1...3- and center sound insulation.
  3. Place drip tray V.A.G 1306 under engine.
  4. Turn drain plug (arrow) on radiator counter-clockwise. If necessary install a drain hose to connection.
  5. In addition, remove lower coolant hose at After-run coolant pump -V51- and drain remaining coolant.
  6. Disconnect electrical connector -1-.
  7. Disconnect coolant hose -2-.
  8. Pull After-run coolant pump -V51- downward out of rubber retainers. If necessary, spray with silicone-free lubricant.

Installation is performed in the reverse order. Note the following

  1. Fill cooling system. See «COOLING SYSTEM, DRAINING AND FILLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .

Radiator and coolant fan, component overview

Note. The following list refers to items in (Scheme 57).

  1. Coolant fan -V7- Removing and Installing, see «COOLANT FAN -V7- AND COOLANT FAN -2- -V177-, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe__coolant-fan-v7-and-coolant-fan)
  2. Retaining clips For electrical wiring going to fans Check for firm attachment
  3. Coolant Fan Control (FC) thermal switch -F18- Tighten to 35 Nm
  4. Seal Replace
  5. Coolant hose To disconnect, release retaining clip
  6. O-ring Replace
  7. Radiator Removing and Installing, see «RADIATOR, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) After replacing, fill with new coolant
  8. 15 Nm
  9. Bracket for radiator Note installed position
  10. 10 Nm
  11. 10 Nm
  12. Radiator cowl
  13. Coolant fan -2- -V177- Removing and Installing, see «COOLANT FAN -V7- AND COOLANT FAN -2- -V177-, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe__coolant-fan-v7-and-coolant-fan)

Scheme 56

Scheme 56
Scheme 56
  1. Hose clip pliers V.A.G 1921
  2. Drip tray V.A.G 1306

Scheme 57

Scheme 57
Scheme 57

Removing And Installing

WARNINGCover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.

Scheme 58

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Scheme 75
Scheme 75
  1. Open filler cap on coolant expansion tank.
  2. Remove fasteners -1- at lock carrier, press pin -2- in approx. 4 mm (do not push in completely). Then pull fastener out upward.
  3. Remove covers (left side) -1- and -2- at lock carrier and above main fuse box (arrows).
  4. Remove covers (right side) -1- and -2- at lock carrier and above coolant expansion tank (arrows).
  5. Remove upper securing bolts (upper arrows) for radiator cowl.
  6. Release tension of poly V-belt by screwing an M8 x 40 bolt (arrow) into bore on tensioning element. NOTE: Mark the rotation direction of the poly V-belt with chalk or a felt-tipped pen. If the belt runs in the opposite direction when it is reinstalled, breakage can result.
  7. Disconnect secondary air hose at position marked with an arrow.
  8. Move air hose clear.
  9. Remove fasteners -1...3- and remove sound insulation.
  10. Remove left sound insulation (arrows).
  11. Remove right sound insulation (arrows).
  12. Remove cross piece (arrows).
  13. Remove power steering pump pulley (counterhold with mandrel).
  14. Remove bolts (arrows) and remove power steering pump from bracket.
  15. Hang power steering pump on lock carrier with hydraulic hoses -1- and -2- attached.
  16. Disconnect electrical connector -1- at Secondary Air Injection (AIR) pump motor -V101-.
  17. Move wiring clear.
  18. Remove bolt -2- for coolant hose bracket.
  19. Remove bolt -3- for secondary air pump air filter.
  20. Remove bolts -1- and -2- and remove secondary air pump with bracket -A-.
  21. Turn drain plug -1- on radiator counter-clockwise and drain coolant. If necessary, fit auxiliary hose to connection.
  22. Release retaining clip -2- for lower coolant hose and disconnect coolant hose from radiator.
  23. Disconnect electrical connectors -1- for coolant fans at bottom of radiator cowl.
  24. Unscrew lower securing bolts (lower arrows) for radiator cowl. (Scheme 73)
  25. Remove radiator cowl with both fans from below.
  26. Disconnect connector -2- at Coolant Fan Control (FC) thermal switch -F18-. CAUTION: The air conditioning refrigerant circuit must not be opened.
  27. Remove refrigerant line -1- at radiator. NOTE: To prevent damage to the condenser and the refrigerant lines/hoses, ensure that lines and hoses are not stretched, kinked or bent.
  28. Remove upper coolant hose -1- at radiator.
  29. Remove front bumper cover. See «Front bumper»(/audi/tt/8n-2003-2006/remont/door-locks-anti-theft-systems/#body-exterior).
  30. Remove securing bolts -1- for condenser.
  31. Remove securing bolts -2- for radiator.
  32. Remove Coolant Fan Control (FC) module -J293- at longitudinal member (left side) in front of battery.
  33. Remove bolts for lock carrier at front.
  34. Loosen upper bolts for lock carrier 2 turns.

Installation is performed in the reverse order. Note the following

Scheme 76

Scheme 76: Installing
Scheme 76: Installing
  1. Install brackets -3- and -4- on radiator as shown.
  2. Install radiator.
  3. Fit securing bolts for radiator (help of a second technician is required).
  4. Install secondary air injection pump. See «SECONDARY AIR INJECTION PUMP, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/exhaust/#exhaust-system-emission-controls-32l-v6-4v-bhe) .
  5. Install power steering pump. See «Power steering gear, removing and installing»(/audi/tt/8n-2003-2006/remont/differentials-drive-axles/#suspension-wheels-steering__power-steering-gear-removing-and-installing) .
  6. Install cross piece.
  7. Install front bumper cover. See «Front bumper»(/audi/tt/8n-2003-2006/remont/door-locks-anti-theft-systems/#body-exterior) .
  8. Replace O-rings in connections for radiator hoses.
  9. Fill cooling system. See «COOLING SYSTEM, DRAINING AND FILLING»(/audi/tt/8n-2003-2006/remont/cooling-system-mechanical/#engine-cooling-system-32l-v6-4v-bhe) .
ComponentNm
Radiator cowl to radiator10
Thermal switch to radiator35
Refrigerant line to radiator10
Condenser to radiator10
Radiator to lock carrier15

TIGHTENING TORQUES: RADIATOR

Special Tools and Equipment

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

Scheme 77

Scheme 77
Scheme 77

Requirement

  1. Engine at operating temperature.

Work sequence

WARNINGCover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.

Scheme 78

Scheme 78
Scheme 78
  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.

If pressure drops

  1. Detect leak and repair malfunction.

Scheme 79

Scheme 79: Pressure relief valve in filler cap, checking
Scheme 79: Pressure relief valve in filler cap, checking
  1. Attach VAG1274 cooling system tester together with VAG1274/9 adapter to filler cap.
  2. Pump using hand pump. Pressure release valve must open at a positive pressure of 1.4 to 1.6 bar.

If the pressure relief valve does not open as described

  1. Replace filler cap.

Coolant fan -V7- and Coolant fan -2- -V177-, removing and installing

WARNINGCover cap of expansion tank with rag and open carefully, as hot steam i.e. hot coolant may escape when opening.

Scheme 80

Scheme 80
Scheme 80

Scheme 81

Scheme 81
Scheme 81

Scheme 82

Scheme 82
Scheme 82

Scheme 83

Scheme 83
Scheme 83

Scheme 84

Scheme 84
Scheme 84

Scheme 85

Scheme 85
Scheme 85

Scheme 86

Scheme 86
Scheme 86

Scheme 87

Scheme 87
Scheme 87

Scheme 88

Scheme 88
Scheme 88

Scheme 89

Scheme 89
Scheme 89

Scheme 90

Scheme 90
Scheme 90

Scheme 91

Scheme 91
Scheme 91

Scheme 92

Scheme 92
Scheme 92

Scheme 93

Scheme 93
Scheme 93
  1. Open filler cap on coolant expansion tank.
  2. Remove fasteners -1- at lock carrier by pressing in pin -2- approx. 4 mm (do not push in completely). Then pull fastener out upward.
  3. Remove covers (left side) -1- and -2- at lock carrier and above main fuse box (arrows).
  4. Remove covers (right side) -1- and -2- at lock carrier and above coolant expansion tank (arrows).
  5. Remove upper securing bolts (upper arrows) for radiator cowl.
  6. Release tension of poly V-belt by screwing an M8 x 40 bolt (arrow) into bore on tensioning element. NOTE: Mark the rotation direction of the poly V-belt with chalk or a felt-tipped pen. If the belt runs in the opposite direction when it is reinstalled, this can cause breakage.
  7. Disconnect secondary air hose at position marked with an arrow.
  8. Move air hose clear.
  9. Remove fasteners -1...3- and remove sound insulation.
  10. Remove left sound insulation (arrows).
  11. Remove right sound insulation (arrows).
  12. Remove cross piece (arrows).
  13. Remove power steering pump pulley (counterhold with mandrel).
  14. Remove bolts (arrows) and remove power steering pump from bracket.
  15. Hang power steering pump on lock carrier with hydraulic hoses -1- and -2- attached.
  16. Disconnect electrical connector -1- at Secondary Air Injection (AIR) pump motor -V101-. (Scheme 92)
  17. Move wiring clear.
  18. Remove bolt -2- for coolant hose bracket. (Scheme 92)
  19. Remove bolt -3- for secondary air pump air filter. (Scheme 92)
  20. Remove bolts -1- and -2- and remove secondary air pump with bracket -A-.
  21. Disconnect electrical connectors -1- for coolant fans at bottom of radiator cowl. see scheme 94
  22. Unscrew lower securing bolts (lower arrows) for radiator cowl.
  23. Disconnect electrical connector -1-.
  24. Move wiring clear.
  25. Remove nuts (arrows) and remove fans.

Installation is performed in the reverse order. Note the following

  1. Install secondary air pump. See «SECONDARY AIR INJECTION PUMP, REMOVING AND INSTALLING»(/audi/tt/8n-2003-2006/remont/exhaust/#exhaust-system-emission-controls-32l-v6-4v-bhe) .
  2. Install power steering pump. See «Power steering gear, removing and installing»(/audi/tt/8n-2003-2006/remont/differentials-drive-axles/#suspension-wheels-steering__power-steering-gear-removing-and-installing) .
  3. Install cross piece.
  4. Install poly V-belt. See «POLY V-BELT, REMOVING AND INSTALLING»(ref-200989-S10536469982005102400000) .
ComponentNm
Coolant fan to radiator cowl10
Radiator cowl to radiator10

TIGHTENING TORQUES: COOLANT FAN

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