3.2l v6 4v Fuel Injection & Ignition, Engine Code(s): Bhe Audi TT 8N рестайлинг

Safety precautions

To reduce the risk of personal injury and/or damage to the fuel injection and ignition system, always observe the following

1. Always switch off ignition before disconnecting or connecting lines of the fuel injection and ignition system, including test leads.
2. If engine is to be cranked at starting RPM without starting (e.g. for compression testing), remove fuse 28 from the fuse carrier and disconnect connectors from ignition coils with assembly tool T10118.
3. During some of the tests, a fault may be recognized and stored by the control module. At the end of all tests and repairs, the fault memory should be checked and, if necessary, erased.
4. Always switch ignition off before cleaning engine.

1. Always witch off the ignition before connecting or disconnecting the battery or the engine control module may be damaged.

Note the following if testers and measuring instruments have to be used during a road test

Rules for cleanliness

When working on the fuel supply/injection system, pay careful attention to the following 6 cleanliness rules

1. Thoroughly clean all unions and adjacent areas before disconnecting.
2. Place removed parts on a clean surface and cover. Use lint-free cloths.
3. Carefully cover or seal open components if repairs cannot be carried out immediately.
4. Install clean components: Remove replacement parts from packaging immediately prior to installation. Do not use parts that have been stored loose (e.g. in tool boxes etc.).

1. When the system is open: Do not work with compressed air if this can be avoided. Do not move vehicle unless absolutely necessary.
2. Separated electrical connectors: Protect from dirt and moisture. Make sure connections are dry when re-connecting.

Technical data

Scheme 7

1 - 3-pin connector

1. For Knock Sensor (KS) 1 -G61

2 - Knock Sensor (KS) 1 -G61

1. Location. See «Location of Knock Sensor (KS) 1 -G61»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

3 - Heated Oxygen Sensor (HO2S) -G39- before catalytic converter and Oxygen Sensor (O2S) Heater -Z19

1. Location. See «Location of oxygen sensors before catalytic converter»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)
2. Removing and installing. Refer to «Oxygen sensors before catalytic converter, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__oxygen-sensors-before-catalytic-converter-removing)

4 - Oxygen Sensor (O2S) behind Three Way Catalytic Converter (TWC) -G130- and Oxygen Sensor (O2S) Heater 1 -Z29

1. Location. (Scheme 7)
2. Removing and installing. Refer to «Oxygen sensors behind catalytic converter, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__oxygen-sensors-behind-catalytic-converter-removing)

5 - Motronic Engine Control Module (ECM) -J220

1. Removing and installing. Refer to «Engine control module, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__engine-control-module-removing-and-installing)

6 - Heated Oxygen Sensor (HO2S) 2 -G108- and Oxygen Sensor (O2S) 2 Heater -Z28

1. Location. See «Location of oxygen sensors before catalytic converter»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)
2. Removing and installing. Refer to «Oxygen sensors before catalytic converter, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__oxygen-sensors-before-catalytic-converter-removing)

7 - Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2 -Z30

1. Location. (Scheme 7)
2. Removing and installing. Refer to «Oxygen sensors behind catalytic converter, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__oxygen-sensors-behind-catalytic-converter-removing)

8 - Positive Crankcase Ventilation (PCV) heating element -N79

9 - Throttle valve control module -J338

1. With Throttle drive (power accelerator activation) -G186-, Angle sensor -1- for throttle drive (power accelerator activation) -G187- and Angle sensor -2- for throttle drive (power accelerator activation) -G188

10 - Instrument cluster

1. With Malfunction Indicator Lamp (MIL) -K83

11 - Throttle Position (TP) sensor -G79- and Accelerator pedal position sensor 2 -G185

1. Location. See «Location of Throttle Position (TP) sensor -G79- and Accelerator pedal position sensor 2 -G185»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

12 - Brake light switch -F- and Brake pedal switch -F47

1. Location. See «Location of Brake light switch -F- and Brake pedal switch -F47»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

13 - Fuel Pump (FP) relay -J17

1. Location. See «Location of Fuel Pump (FP) relay -J17»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

14 - Secondary Air Injection (AIR) pump relay -J299

1. Location. See «Location of Motronic ECM power supply relay -J271- and Secondary Air Injection (AIR) pump relay -J299»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

15 - Motronic ECM power supply relay -J271

16 - Mass Air Flow (MAF) sensor -G70

17 - Camshaft Position (CMP) sensor 2 -G163

1. Black connector

18 - Camshaft adjustment valve 1 (exhaust)

1. Brown connector

19 - Valve -1- for camshaft adjustment -N205

1. Black connector

20 - Camshaft Position (CMP) sensor -G40

1. Black connector

21 - Engine Coolant Temperature (ECT) sensor -G62

1. Location. See «Location of Engine Coolant Temperature (ECT) sensor -G62»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)
2. If necessary, release cooling system pressure before removal

22 - Engine speed (RPM) sensor -G28

1. Location. See «Location of Engine speed (RPM) sensor -G28- with 3-pin connector»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

23 - Vacuum unit for intake manifold change-over

24 - Fuel pressure regulator

1. Checking. Refer to «Fuel system pressure, pressure regulator and holding pressure, checking»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

25 - Secondary Air Injection (AIR) pump motor -V101

26 - Intake manifold change-over valve -N156

1. Location. See «Location of Intake manifold change-over valve -N156»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

27 - Secondary Air Injection (AIR) solenoid valve -N112

1. Location. See «Location of Secondary Air Injection (AIR) solenoid valve -N112»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

28 - Knock Sensor (KS) 2 -G66

1. Location. See «Location of Knock Sensor (KS) 2 -G66»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

29 - 3-pin connector

1. For Engine speed (RPM) sensor -G28
2. Location. See «Location of Engine speed (RPM) sensor -G28- with 3-pin connector»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

30 - Ignition coils with output stages

1. Cylinder 1 ignition coil 1 with output stage -N70
2. Cylinder 2 ignition coil 2 with output stage -N127
3. Cylinder 3 ignition coil 3 with output stage -N291
4. Cylinder 4 ignition coil 4 with output stage -N292

1. Cylinder 5 ignition coil 5 with output stage -N323
2. Cylinder 6 ignition coil 6 with output stage -N324

31 - Fuel injectors

1. Cylinder 1 injector, cylinder 1 -N30
2. Cylinder 2 injector, cylinder 2 -N31
3. Cylinder 3 injector, cylinder 3 -N32
4. Cylinder 4 injector, cylinder 4 -N33

1. Cylinder 5 injector, cylinder 5 -N83
2. Cylinder 6 injector, cylinder 6 -N84
3. Checking injection quantity and spray pattern, checking for leaks. Refer to «Injection quantity, leak tightness and spray pattern of injectors, checking»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)
4. Removing and installing. Refer to «Fuel injectors, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__fuel-injectors-removing-and-installing)

32 - Evaporative Emissions (EVAP) canister purge regulator valve -N80

Scheme 8

Scheme 9

1. On pedal bracket

Scheme 10

1. In front exhaust pipe

1 - Heated Oxygen Sensor (HO2S) 2 -G108- and Oxygen Sensor (O2S) 2 Heater -Z28

2 - Heated Oxygen Sensor (HO2S) -G39- and Oxygen Sensor (O2S) Heater -Z19

Scheme 11

1. In catalytic converter

1 - Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2 -Z30

2 - Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130- and Oxygen Sensor (O2S) Heater 1 -Z29

Scheme 12

1. In micro central electrics (left side) under instrument panel: position 4

Scheme 13

1. Beneath cover on left at bulkhead

1 - Secondary Air Injection (AIR) pump relay -J299

2 - Motronic ECM power supply relay -J271

Note. To remove dust cover, unfasten relay carrier at bulkhead and lower.

Scheme 14

1 - 3-pin connector

2 - Engine speed (RPM) sensor -G28

Scheme 15

1. At vacuum reservoir (at front of engine)

Scheme 16

1. At vacuum reservoir (at front of engine)

Scheme 17

1. At front left on cylinder head

Scheme 18

1. At right rear on cylinder block

1 - Knock Sensor (KS) 1 -G61

2 - 3-pin connector

Scheme 19

1. At front on cylinder block

Scheme 20

1 - Seal

2 - Mass Air Flow (MAF) sensor -G70

3 - Cross-head screw

4 - Air intake hose

5 - 5-pin connector

6 - Cross-head screw

7 - Air cleaner housing (upper section)

8 - Filter element

9 - Nut, 10 Nm

10 - Air intake connection

11 - Air cleaner housing (lower section)

12 - Bolt, 10 Nm

Scheme 21

1 - Change-over mechanism

2 - Bushing

3 - O-ring

1. Replace

4 - Panel bolt

5 - Bearing cap

6 - Intake manifold

7 - 20 Nm

8 - 20 Nm

9 - Seal

10 - Connection for crankcase breather

1. With Positive Crankcase Ventilation (PCV) heating element -N79

11 - O-ring

12 - Throttle valve control module -J338

13 - 10 Nm

14 - 20 Nm

15 - Heat shield for exhaust manifold

1. With support for intake manifold

16 - Gasket

1. Replace
2. Insert into manifold

17 - 13 Nm

18 - Panel bolt

19 - Vacuum unit

20 - Vacuum connection

1. To Intake manifold change-over valve -N156

21 - O-ring

1. Replace

22 - Bushing

Removing

Note. Replace all cable ties which are opened or cut open when removing the engine. Reinstall the cable ties in the same position when installing the engine.

1. Note coding on vehicles with coded radio/radio navigation system; if necessary, obtain correct coding.

Scheme 22

1. With ignition switched off, disconnect Ground cable (arrow) at battery (in luggage compartment under floor cover).

Scheme 23

1. To remove fasteners -1- at lock carrier, press pin -2- in approx. 4 mm (do not push in completely). Then pull fastener out upward.

Scheme 24

1. Remove covers (left side) -1- and -2- at lock carrier and above main fuse box (arrows).

Scheme 25

1. Remove covers (right side) -1- and -2- at lock carrier and above expansion tank (arrows).
2. Pull out dipstick.

Note. Before removing, mark direction of rotation of poly V-belt with chalk or felt-tipped pen. If the belt runs in the opposite direction when it is reinstalled, breakage can result.

Scheme 26

1. To release tension of poly V-belt, screw a bolt M8 x 40 (arrow) into bore on tensioning element.
2. Remove poly V-belt from Generator pulley.

Scheme 27

1. Remove upper securing bolt -2- for Generator.

Scheme 28

1. Remove both bolts (upper arrows) securing radiator cowl.

Scheme 29

1. Disconnect air hose from secondary air injection pump at position marked with arrow.
2. Move air hose clear.

Scheme 30

1. Remove fasteners -1 to 3- and center sound insulation.

Scheme 31

1. Remove right sound insulation (arrows).

Scheme 32

1. Remove left sound insulation (arrows).

Scheme 33

1. Remove cross piece (arrows).
2. Unbolt pulley for power steering pump (counterhold with mandrel).

Scheme 34

1. Remove power steering pump from bracket (arrows).
2. Hang power steering pump on lock carrier with hydraulic hoses -1- and -2- attached.

Scheme 35

1. Disconnect electrical connector (arrow) at Secondary Air Injection (AIR) pump motor -V101-.
2. Move wire clear.
3. Remove bracket -2- for coolant hose.
4. Remove bracket -3- for secondary air pump air filter.

Scheme 36

1. Remove bolts -1- and -2- and remove secondary air injection pump with bracket -A-.

1. Disconnect electrical connectors -1- for coolant fan on lower left of radiator cowl.
2. Remove bolts on radiator cowl (lower arrows). Bolts are accessible from below.
3. Remove radiator cowl with both fans from below.

Scheme 37

1. Disconnect electrical connector -1- for air conditioning compressor clutch.

1. Remove bolts (arrow) for air conditioning compressor.
2. Tie up air conditioning compressor together with refrigerant hoses at front of longitudinal member (refrigerant hoses remain connected).

Note. The air conditioning compressor can only be removed from the bracket with the upper securing bolt still inserted. To do so, press the engine simultaneously to the left side with an assembly lever (2nd technician required).

1. Remove lower securing bolt for Generator.
2. Remove Generator from bracket (electrical wiring remains attached).

Scheme 38

1. Remove clamp -3-.
2. Remove wire connection -1- at Generator.
3. Disconnect electrical connector -2-.
4. Remove Generator.

Scheme 39

1. Remove bolt -3- and pull out guide tube for oil dipstick -2-.
2. Remove bolt -4- and unfasten vacuum reservoir -1- from manifold.
3. Move vacuum reservoir to side (hoses remain attached).

Scheme 40

1. Remove bolt (arrow) at coolant pump bracket for After-Run coolant pump -V51-.
2. Remove bolts -1 to 5- and remove bracket for ancillary units.

Scheme 41

1. Remove bolts (arrows) at front of intake manifold.

Scheme 42

1. Disconnect electrical connectors at ignition coils by releasing tab (arrow) with assembly tool T10118 and carefully pulling connector.

Scheme 43

1. Attach puller T10095 A to ignition coils as shown in illustration (arrow) and remove ignition coils one at a time.

Scheme 44

1. Remove body brace -1- (arrows).

Scheme 45

1. Move electrical wire (arrow) clear.
2. Loosen hose clamps -1- and -2- and remove air hose between air cleaner housing and Throttle valve control module -J338-.

Scheme 46

1. Disconnect electrical connectors -2- and -3-.
2. Disconnect crankcase breather hose -1-.

Scheme 47

1. Remove bolts and remove Throttle valve control module -J338- (arrows) from intake manifold and move clear to one side (hoses remain attached).

Scheme 48

1. Disconnect vacuum hoses -1 to 4- at rear of intake manifold.

Note. The other hoses remain attached on hose bracket.

1. Remove hose bracket from intake manifold (arrows).

Scheme 49

1. Remove rear securing bolts (arrows) for intake manifold.

Scheme 50

1. Protect intake manifold from damage with a clean cloth -1-.
2. Swing intake manifold forward (arrow)

Note. Cover or plug the intake ports in the cylinder with a clean cloth or foam to prevent small items from falling in.

Disconnecting Vacuum Hose At Vacuum Unit For Intake Manifold Change-Over. Scheme 51

1. Disconnect vacuum hose (arrow) at vacuum unit for intake manifold change-over.

Scheme 52

1. Unclip pipe guide -1- from fuel rail -2-.
2. Disconnect vacuum pipe -3- from fuel pressure regulator.
3. Unscrew bolts (arrows).
4. Remove fuel rail with fuel injectors from cylinder head and move clear to one side (fuel lines remain attached).

1. Swing intake manifold back to its installed position and remove.

Installing

Installation is performed in reverse order. Note the following

Note. Replace gaskets.

1. Install bracket for ancillary units.

Refer to 13 ENGINE - CRANKSHAFT, CYLINDER BLOCK

1. Install Generator.

Refer to 27 BATTERY, STARTER, GENERATOR, CRUISE CONTROL

1. Install air conditioning compressor.

Refer to 87 AIR CONDITIONING

1. Install radiator cowl.

Refer to 19 ENGINE - COOLING SYSTEM

1. Install secondary air injection pump.

Refer to 26 - EXHAUST SYSTEM, EMISSION CONTROLS

1. Install body brace and cross piece.

Refer to 40 FRONT SUSPENSION

1. Install power steering pump.

Refer to 48 STEERING

1. Install poly V-belt.

Refer to 13 ENGINE - CRANKSHAFT, CYLINDER BLOCK

Note. When the battery is reconnected, please ensure that the vehicle equipment (e.g. radio, radio/navigation system, clock, power windows) is activated as described in the operating instructions.

Tightening torques

Wiring and component check on engine control module with test box VAG1598/31

Special tools and equipment required

Scheme 53

1. Test box V.A.G 1598/31

Note. The test box VAG1598/31 is designed in such a way to be connected simultaneously to the engine control module wiring harness and to the engine control module. This has the advantage that the electronic engine control system remains fully functional when the test box is connected (for example, for measuring signals when the engine is running). Whether the engine control module has to be connected to the test box or not is described in the respective test procedures. Always use adapter set V.A.G 1594 A to connect test equipment (e.g. voltage tester - V.A.G 1527 B, multimeter V.A.G 1526 A, etc.).

Work sequence

1. Remove engine control module. Refer to «Engine control module, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__engine-control-module-removing-and-installing) .

Note. If the test box V.A.G 1598/31 only needs to be attached to the 81-pin connector, the protective housing for the engine control module does not need to be removed

Scheme 54

1. Connect VAG1598/31 test box to connectors of wiring harness.
2. Connect Ground clamp on test box to Ground (arrow).

Note. Whether or not the engine control module has to be connected to the test box is described in the respective test procedures.

1. Perform test as described in relevant repair procedures.
2. After completing test, reinstall engine control module. Refer to «Engine control module, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__engine-control-module-removing-and-installing) .

Engine control module, removing and installing

The protective housing has to be removed before the 60-pin connector can be disconnected from the control module (e.g. to connect the test box or replace the engine control module).

Special tools and equipment required

Scheme 55

1. Puller T10130

Removing

Note. When replacing the engine control module, select the diagnosis object "Replace engine control module" in "Guided Fault Finding". For this purpose, use the vehicle diagnostic, testing and information system VAS 5051 A.

1. Switch off ignition and remove ignition key.

Scheme 56

1. Use screwdriver to pry off covers at wiper arms (arrows) and unscrew hex nuts.

Scheme 57

1. Use puller T10130 to remove wiper arms -1- from wiper shafts.

Scheme 58

1. Pull off rubber seal -1- on plenum chamber cover.
2. Remove plenum chamber cover -2- and lay aside (toward windshield).
3. Disconnect electrical connectors for windshield washer heating.

Scheme 59

1. Unclip cover -2-.
2. Disconnect multiple connectors -1- and -3- at engine control module.
3. Release retaining tab (arrow) and pull engine control module forward out of bracket.

Installing

Installation is performed in the reverse order of removal. After the installation of a new engine control module, perform the following operations

1. Activate engine control module in "Guided Fault Finding" under diagnosis option "Replace engine control module".

Note. For this purpose, use the vehicle diagnostic, testing and information system VAS 5051 A.

Scheme 60

Note. The fuel pressure regulator regulates the fuel pressure according to the intake manifold pressure. The pressure drop at the injectors remains constant for each engine speed and load range.

Special tools and equipment required

1. Pressure gauge V.A.G 1318
2. Adapter set V.A.G 1318/17
3. Hose clamp pliers V.A.G 1921

Requirements

1. Fuel pump relay OK
2. Fuel pump OK; checking

Refer to 20 - FUEL SUPPLY

1. Fuel filter OK
2. Battery voltage at least 12.7 V

Checking system pressure

1. Briefly open fuel tank filler cap (to release pressure).

Scheme 61

1. Open cover of use carrier and remove fuse 28 for Fuel pump -G6- (pre-supply pump).

Scheme 62

1. Disconnect fuel supply line -1- by pressing release tab.

Scheme 63

1. Connect pressure gauge V.A.G 1318 with adapters V.A.G 1318/9 and V.A.G 1318/17 to fuel supply line.
2. Open cut-off valve on pressure gauge. Lever must point in direction of flow.
3. Reinstall fuse 28 for Transfer Fuel Pump (FP) -G6- (pre-supply pump) in fuse carrier.
4. Start engine and run at idling speed.

1. Measure fuel pressure

Specification: approx. 3.5 bar

Scheme 64

1. Disconnect vacuum hose at fuel pressure regulator.

Fuel pressure must increase to approx. 4.0 bar

1. Switch off ignition.
2. Check for leaks and residual pressure by watching drop in pressure on pressure gauge.

After 10 minutes pressure must still be at least 3.0 bar

If the residual pressure drops below 3.0 bar

1. Start engine and run at idling speed.

Scheme 65

1. Allow pressure to build up, then switch off ignition. Simultaneously, close cut-off valve of pressure gauge V.A.G 1318 (lever perpendicular to direction of flow - arrow-)
2. Observe pressure drop on pressure gauge.

If the pressure now does not drop

1. Check fuel pump non-return valve.

If the pressure drops again

1. Open cut-off valve on pressure gauge (lever points in direction of flow).
2. Start engine and run at idling speed.
3. Allow pressure to build up, then switch off ignition. Simultaneously, tightly clamp off return hose (with blue marking).

If the pressure now does not drop

1. Replace fuel pressure regulator.

If the pressure drops again

1. Check line connections, O-rings on fuel rail and injectors for leaks.
2. Check pressure gauge for leaks.

Note. Before removing the pressure gauge, release the fuel pressure by opening the cut-off valve. Hold a container under the connection.

Scheme 66

1 - Fuel return hose

2 - Fuel supply hose

3 - Fuel rail

4 - Hex socket head bolt, 10 Nm

5 - Fuel pressure regulator

6 - O-ring

7 - O-ring

8 - Retaining clip

1. Check for correct fit on fuel rail

9 - O-ring

1. Removing and installing. Refer to «Fuel injectors, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__fuel-injectors-removing-and-installing)
2. Replace
3. Lubricate with clean engine oil

10 - Retaining clip

1. Check for correct fit on fuel rail

11 - O-ring

1. Removing and installing. Refer to «Fuel injectors, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__fuel-injectors-removing-and-installing)
2. Replace
3. Lubricate with clean engine oil

12 - Fuel injector

Fuel injectors, removing and installing

Removing

1. Remove intake manifold. Refer to «Intake manifold, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe) .

1. Disconnect fuel supply line -1- and fuel return line -2- by pressing release tabs.
2. Remove fuel rail together with injectors. Refer to «Fuel rail with injectors, disassembling and assembling»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe) . Fuel hoses remain connected.
3. Pull off retaining clip and remove injector.

Note. The fuel hoses must be disconnected before replacing the fuel rail.

Installing

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

1. Replace O-rings at all opened connections. (When replacing front O-ring, ensure that plastic cap is not removed from injector head. O-ring must be pulled off over plastic cap).
2. Lubricate O-rings with clean engine oil.
3. Make sure injectors are installed in correct position.
4. Make sure retaining clips are properly connected.

1. Position fuel rail with secured injectors on intake manifold and press evenly into place.

Tightening torque

Scheme 67

Special tools and equipment

1. Remote control V.A.G 1348/3 A with adapter cable V.A.G 1348/3-2
2. Adapter set V.A.G 1594 A
3. Injection rate tester V.A.G 1602
4. Test box V.A.G 1598/31

Requirements

1. Fuel pressure OK; checking. Refer to «Fuel system pressure, pressure regulator and holding pressure, checking»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe)

Work sequence

1. Remove intake manifold. Refer to «Intake manifold, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe) .
2. Remove fuel rail together with injectors. Refer to «Fuel rail with injectors, disassembling and assembling»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe) . Fuel hoses remain connected.

Checking for leaks

1. Open cover of fuse carrier and remove fuse 28 for Fuel pump -G6- (pre-supply pump).
2. Connect remote control V.A.G 1348/3 A with adapter cable V.A.G 1348/3-2 to contact 28a for fuel pump and to positive (+) battery terminal.
3. Connect battery cable Ground cable.
4. Activate remote control V.A.G 1348/3 A. Fuel pump must run.

1. Visually check fuel injectors for leaks.

When fuel pump is running, no more than 1 to 2 drops per minute should escape from any one injector.

If fuel loss is greater

1. Replace faulty injector. Refer to «Fuel injectors, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__fuel-injectors-removing-and-installing) .

Checking injection quantity

1. Connect test box V.A.G 1598/31 to wiring harness for engine control module. Refer to «Wiring and component check on engine control module with test box VAG1598/31»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__wiring-and-component-check-on-engine) . Engine control module is not connected.
2. Use leads from adapter set V.A.G 1594 A to bridge contacts 1 and 65 at test box.

Scheme 68

1. Disconnect electrical connectors for fuel injectors by pressing retaining tab in direction of arrow.
2. Place a fuel injector in measuring glass of injection rate tester V.A.G 1602.

Scheme 69

1. Connect one contact of fuel injector to engine Ground using test lead and alligator clamp from adapter set V.A.G 1594 A.
2. Connect second contact of fuel injector to remote control V.A.G 1348/3 A with adapter cable V.A.G 1348/3-2.
3. Connect alligator clamp to positive (+) battery terminal.
4. Use leads from adapter set V.A.G 1594 A to bridge contacts 1 and 65 at test box.

1. If necessary, connect battery Ground cable.
2. Switch ignition on.

Fuel pump should run

1. Activate remote control VAG1348/3 A for 30 seconds.
2. Perform test for all injectors using a new glass each time.

Note. When checking the injection quantity, also check the spray pattern. The spray pattern should be the same for all the injectors.

1. Once all 6 injectors have been actuated, place measuring glasses on a level surface.

1. Specification: 128 to 140 ml for each injector

If measured values for one or more injectors are outside specification

1. Stop fuel pump (switch off ignition) and replace faulty injector. Refer to «Fuel injectors, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__fuel-injectors-removing-and-installing) .

If measured values for all the injectors are outside specification

1. Check fuel pressure. Refer to «Fuel system pressure, pressure regulator and holding pressure, checking»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe) .
2. Install injectors with fuel rail. Refer to «Fuel rail with injectors, disassembling and assembling»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe) .

Oxygen sensors before catalytic converter, removing and installing

Special tools and equipment required

Scheme 70

1. Ring spanner 7-piece set 3337

Removing

1. Remove body brace -1- (arrows).

1. Loosen oxygen sensor to be removed about 1 turn (accessible from above).

1 - Heated Oxygen Sensor (HO2S) 2 -G108- and Oxygen Sensor (O2S) 2 Heater -Z28

2 - Heated Oxygen Sensor (HO2S) -G39- and Oxygen Sensor (O2S) Heater -Z19

1. Remove fasteners -1 to 3- and center sound insulation.

Scheme 71

1. Unbolt protective cover (arrows).
2. Disconnect electrical connector for oxygen sensor (before catalytic converter) that is to be removed and move clear to side.

1. Unscrew oxygen sensor (before catalytic converter) from below; ensure that electrical wire is not damaged when removing.

1 - Heated Oxygen Sensor (HO2S) 2 -G108- and Oxygen Sensor (O2S) 2 Heater -Z28

2 - Heated Oxygen Sensor (HO2S) -G39- and Oxygen Sensor (O2S) Heater -Z19

Installing

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

Note. The threads of the new oxygen sensors are already coated with assembly paste. The paste must not get into the slots on the sensor body. If reinstalling the old oxygen sensors, coat the threads with high-temperature paste. The paste must not get into the slots on the sensor body. When installing, the oxygen sensor wire must always be reattached at the same locations to prevent the wire from coming into contact with the exhaust pipe. Secure the heat insulations sleeves in the original position when installing

Tightening torques

Oxygen sensors behind catalytic converter, removing and installing

Special tools and equipment required

1. Ring spanner 7-piece set 3337

Work sequence

1. Remove bolts and take off protective cover (arrows).
2. Disconnect electrical connector for oxygen sensor (behind catalytic converter) that is to be removed and move clear to side.

Oxygen sensor (right side)

Scheme 72

1. Remove fasteners for wiring guide (arrows).

Continuation for both sides

1. Remove oxygen sensor (behind catalytic converter). Ensure that electrical wire is not damaged when unscrewing sensor.

1 - Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2 -Z30

2 - Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130- and Oxygen Sensor (O2S) Heater 1 -Z29

Installing

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

Note. The threads of the new oxygen sensors are already coated with assembly paste. The paste must not get into the slots on the sensor body. If reinstalling the old oxygen sensors, coat the threads with high-temperature paste. The paste must not get into the slots on the sensor body. When installing, the oxygen sensor wire must always be reattached at the same locations to prevent the wire from coming into contact with the exhaust pipe.

Tightening torques

General notes

1. Switch off the ignition before connecting or disconnecting the battery, otherwise the engine control module may be damaged.
2. A voltage of at least 12.7 V is necessary for satisfactory functioning of the electrical components.
3. During some of the tests, a malfunction may be recognized and stored by the control module. At the end of all tests and repairs, the fault memory should be checked and, erased.
4. If the engine starts and then stops after malfunction search, repair or tests on components, because the immobilizer is blocking the engine control module. The fault memory must then be checked and, if necessary, the control module adapted.

To prevent injuries to persons and/or damage to the fuel injection and ignition system, observe the following

1. Do not touch or disconnect ignition wiring when the engine is running or at starting speed.
2. The ignition must be switched off before connecting or disconnecting ignition system wiring. This also applies to high-voltage cables and measuring instrument leads.
3. During some of the tests, a malfunction may be recognized and stored by the control module. At the end of all tests and repairs, the fault memory should be checked and, erased.
4. Always switch off the ignition before washing the engine.

Scheme 73

1 - Ignition coils with output stages

1. Cylinder 1 ignition coil 1 with output stage -N70
2. Cylinder 2 ignition coil 2 with output stage -N127
3. Cylinder 3 ignition coil 3 with output stage -N291
4. Cylinder 4 ignition coil 4 with output stage -N292

1. Cylinder 5 ignition coil 5 with output stage -N323
2. Cylinder 6 ignition coil 6 with output stage -N324

2 - 4-pin connector

1. For ignition coils with output stage

3 - Bracket

1. For connector for Knock Sensor 1 -G61

4 - Bolt, 10 Nm

5 - 3-pin connector

1. Black
2. With gold-plated contacts

6 - Knock Sensor (KS) 1 -G61

7 - Bolt, 20 Nm

1. To ensure correct operation of knock sensor, it is important to adhere to specified tightening torque

8 - Camshaft adjuster

1. Exhaust side
2. With sender wheel for Camshaft Position sensor 2 -G163
3. After reinstalling, adjust valve timing

Refer to 13 ENGINE - CRANKSHAFT, CYLINDER BLOCK

9 - Cover (upper) for camshaft timing chain

1. Removing and installing

Refer to 13 ENGINE - CRANKSHAFT, CYLINDER BLOCK

10 - Seal

1. Replace

11 - Camshaft Position (CMP) sensor -G163

1. For exhaust camshaft

12 - Bolt, 10 Nm

13 - 3-pin connector

1. Black
2. With gold-plated contacts
3. Mark before removing

14 - Camshaft Position (CMP) sensor -G40

1. For intake camshaft

15 - Knock Sensor (KS) 2 -G66

16 - 2-pin connector

1. Black
2. With gold-plated contacts

17 - Camshaft adjuster

1. Intake side
2. With sender wheel for Camshaft Position sensor -G40
3. After reinstalling, adjust valve timing

Refer to 13 ENGINE - CRANKSHAFT, CYLINDER BLOCK

18 - Spark plug

1. Removing and installing. Refer to «Spark plugs, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__spark-plugs-removing-and-installing)
2. Tighten to 30 Nm

19 - Valve timing housing

1. For variable valve timing
2. Removing and installing

Refer to 13 ENGINE - CRANKSHAFT, CYLINDER BLOCK

Ignition coils, removing and installing

Special tools and equipment required

Scheme 74

1. Puller T10095 A

Scheme 75

1. Assembly tool T10118

Removing

1. Disconnect electrical connectors at ignition coils by releasing tab (arrow) with assembly tool T10118 and pulling connector.

1. Attach puller T10095 A to ignition coils as shown in illustration (arrow) and remove ignition coils one at a time.

Installing

Install in reverse order of removal. Note the following

Scheme 76

1. Insert ignition coils into holes so that flat edges align with one another (arrows).

Spark plugs, removing and installing

Special tools and equipment required

Scheme 77

1. Spark plug socket 3122 B

Removing

1. Remove ignition coils. Refer to «Ignition coils, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__ignition-coils-removing-and-installing) .
2. Remove spark plugs with spark plug socket 3122 B.

Installing

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

1. Install ignition coils. Refer to «Ignition coils, removing and installing»(/audi/tt/8n-2003-2006/remont/ignition-system/#32l-v6-4v-fuel-injection-ignition-engine-codes-bhe__ignition-coils-removing-and-installing) .

Tightening torque

See also:
• 01 ON BOARD DIAGNOSTIC (OBD)
• 13 ENGINE - CRANKSHAFT, CYLINDER BLOCK
• 27 BATTERY, STARTER, GENERATOR, CRUISE CONTROL
• 87 AIR CONDITIONING
• 26 - EXHAUST SYSTEM, EMISSION CONTROLS
• 40 FRONT SUSPENSION
• Location of Knock Sensor (KS) 1 -G61
• Oxygen sensors before catalytic converter, removing and installing
• Oxygen sensors behind catalytic converter, removing and installing
• Engine control module, removing and installing
• Fuel injectors, removing and installing
• Wiring and component check on engine control module with test box VAG1598/31
• Spark plugs, removing and installing
• Ignition coils, removing and installing