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Exhaust System, Emission Controls, Generic Scan Tool (4.2l v8 5v - Art, Awn, Bbd) Audi S6 C5

Exhaust 22 illustrations ~4177 words

Exhaust system components, removing and installing

Note. Always replace gaskets and self-locking nuts. After exhaust system repairs, make sure exhaust system is not under stress and has sufficient clearance from the body. If necessary, loosen clamps and align mufflers and exhaust pipes so that there is adequate distance to vehicle body, and weight is evenly distributed among the exhaust mounts. Decoupling element in front exhaust pipe must not be bent more than 10°, otherwise it may be damaged.

Mufflers with mounts

Note. The following list refers to (Scheme 25).

  1. 40 Nm
  2. From Three Way Catalytic Converter (TWC)
  3. Carriage bolt
  4. Front clamping sleeve Before tightening, align exhaust system tension-free. See «EXHAUST SYSTEM, ALIGNING FREE OF TENSION»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__exhaust-system-aligning-free-of-tension) . Tighten bolts evenly
  5. 25 Nm
  6. Suspended mount With retainer ring Replace if damaged
  7. Center muffler Factory-installed with rear muffler as one unit. If repair is necessary, replace separately
  8. Rear clamping sleeve Used when center or rear muffler is replaced separately. Before tightening, align exhaust system is tension-free. See «EXHAUST SYSTEM, ALIGNING FREE OF TENSION»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__exhaust-system-aligning-free-of-tension) . Installed position. See «INSTALLED POSITION OF REAR CLAMPING SLEEVES»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__installed-position-of-rear-clamping-sleeves) . Tighten bolts evenly
  9. Separating point
  10. Right rear muffler Factory-installed with center muffler as one unit. If repair is necessary, replace separately
  11. Suspended mount Replace if damaged
  12. Bracket
  13. Left rear muffler Factory-installed with center muffler as one unit. If repair is necessary, replace separately

Installed position of front clamping sleeves

  1. Install double clamps so that the bolt ends do not project beyond lower edge of double clamp. Screw connections face each other

Installed position of rear clamping sleeves

  1. Install double clamps so that the bolt ends do not project beyond lower edge of double clamp (arrow).

Three Way Catalytic Converter (TWC), checking

  1. Perform the test in "Mode 6: Check test results of components that are not continuously monitored", as described under "Test-ID 01: Check catalytic converter". See «TEST-ID 01: CATALYTIC CONVERTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

If the specified values are exceeded

  1. Replace the respective front exhaust pipe with catalytic converter: Left front exhaust pipe. See «LEFT FRONT EXHAUST PIPE WITH CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__left-front-exhaust-pipe-with-catalytic) . Right front exhaust pipe. See «RIGHT FRONT EXHAUST PIPE WITH CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__right-front-exhaust-pipe-with-catalytic) .

Recommended special tools and equipment

  1. 3337 wrench, 7-piece set

Removing

  1. Remove corresponding front exhaust pipe: Left front exhaust pipe. See «LEFT FRONT EXHAUST PIPE WITH CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__left-front-exhaust-pipe-with-catalytic) . Right front exhaust pipe. See «RIGHT FRONT EXHAUST PIPE WITH CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__right-front-exhaust-pipe-with-catalytic) .
  2. Unscrew oxygen sensor e.g. using special tool 3337/9.

Installing

Installation is the reverse of removal, noting the following

Note. The threads of new oxygen sensors are coated with assembly paste; the paste must not get into slots of oxygen sensor body. When re-using the old oxygen sensor, grease the threads with hot bolt paste; the paste must not get into slots of oxygen sensor body. Wires of oxygen sensors must always be secured in the same position when installing so that contact with the exhaust pipe is avoided.

Tightening torque

ComponentNm
Oxygen sensor in front exhaust pipe55

OXYGEN SENSOR IN FRONT EXHAUST PIPE TIGHTENING TORQUE

  1. 3337 wrench, 7-piece set
  1. Remove corresponding front exhaust pipe: Left front exhaust pipe. See «LEFT FRONT EXHAUST PIPE WITH CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__left-front-exhaust-pipe-with-catalytic) . Right front exhaust pipe. See «RIGHT FRONT EXHAUST PIPE WITH CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__right-front-exhaust-pipe-with-catalytic) .
  2. Unscrew oxygen sensor e.g. using special tool 3337/9.

Installation is the reverse of removal, noting the following

Note. The threads of new oxygen sensors are coated with assembly paste; the paste must not get into slots of oxygen sensor body. When re-using the old oxygen sensor, grease the threads with hot bolt paste; the paste must not get into slots of oxygen sensor body. Wires of oxygen sensors must always be secured in the same position when installing so that contact with the exhaust pipe is avoided.

ComponentNm
Oxygen sensor in front exhaust pipe55

OXYGEN SENSOR IN FRONT EXHAUST PIPE TIGHTENING TORQUE

Left front exhaust pipe with catalytic converter, removing and installing

Note. Replace gaskets and self-locking nuts. Decoupling element in front exhaust pipe must not be bent more than 10°, otherwise it may be damaged.

Scheme 25

Scheme 25: Removing
Scheme 25: Removing

Scheme 26

Scheme 26
Scheme 26

Scheme 27

Scheme 27
Scheme 27

Scheme 28

Scheme 28
Scheme 28
  1. Remove the center engine cover (arrows).
  2. Remove cover -2- above the left cylinder head.
  3. Remove the air intake tube (arrows) between the air filter and the throttle valve part.
  4. Disconnect the electrical harness connector -2- for oxygen sensor behind catalytic converter and expose wire. NOTE: Secure a binding wire to connector for oxygen sensor behind catalytic converter to facilitate pulling in the wire during installation.
  5. Remove coolant reservoir -3- (arrows)
  6. Disconnect wire from Engine Coolant Level (ECL) Warning Switch -F66- and lay coolant reservoir to side. NOTE: Coolant hoses -1- and -2- remain connected.
  7. Remove harness connector (arrow) for oxygen sensor before catalytic converter from bracket.
  8. Disconnect harness connector and expose wire.
  9. Loosen upper bolt on connection of exhaust manifold / exhaust pipe.
  10. Loosen connecting bolts (arrows) at exhaust manifold / front exhaust pipe from below.
  11. Remove exhaust pipe from bracket (arrow). NOTE: Decoupling element in front exhaust pipe must not be bent more than 10°, otherwise it may be damaged.
  12. Loosen double clamps -1- and -2- of exhaust system and slide them toward rear.
  13. Pull front exhaust pipe at left slightly toward rear.
  14. Remove heat shield for drive shaft -arrows-.
  15. Unbolt driveshaft -1- from transmission and let it rest on heat shield -2-.
  16. Secure driveshaft using wire (arrow) at bracket -3- of fuel lines.
  17. Position Engine-/Gearbox Jack V.A.G 1383 A -Item B- with stand -Item A- under transmission and support transmission. NOTE: For vehicles with automatic transmission, support on transmission housing only and not on ATF pan of transmission.
  18. First remove bolts -1-, then bolts -2-.
  19. Slowly lower the rear subframe slightly using V.A.G 1383 A engine/transmission jack.
  20. Open all cable ties on transmission for wire connections of oxygen sensors behind catalytic converter.
  21. Expose cables.
  22. Carefully remove left exhaust pipe.

Installation is the reverse of removal, noting the following

Note. Wires of oxygen sensors must always be secured in the same position when installing so that contact with the exhaust pipe is avoided. After removing driveshaft, always remove any remaining locking fluid from thread bores in the transmission drive flange. Otherwise there is a possibility that the new bolts may get jammed when installed and shear when removed. Cleaning can be performed with a tap. Always replace driveshaft bolts (self-locking).

  1. Note the different tightening torques when securing the subframe.
  2. Use new bolts when securing.
  3. Tighten bolts -2- to 110 Nm + turn another 90°.
  4. Tighten bolts -1-. Note the different tightening methods for the various bolt versions. (Scheme 43)

Bolt versions

Scheme 29

Scheme 29
Scheme 29

Bolt -A- without ribbing.

Tightening torques: 25 Nm

Bolt -B- with ribbing.

Tightening torques: 75 Nm

Bolt -C- with screw head and washer ribbing.

Tightening torques: 30 Nm + turn another 90°.

  1. Align exhaust system free of stress. See «EXHAUST SYSTEM, ALIGNING FREE OF TENSION»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__exhaust-system-aligning-free-of-tension) .

Tightening torques

ComponentNm
Driveshaft to transmission55
Heat shield for driveshaft to cover for Torsen differential25
Front exhaust pipe with catalytic converter to mounting strap25
Front exhaust pipe with catalytic converter to exhaust manifold25
Clamp for exhaust pipe40

TIGHTENING TORQUES: LEFT FRONT EXHAUST PIPE WITH CATALYTIC CONVERTER

Right front exhaust pipe with catalytic converter, removing and installing

Note. Replace gaskets and self-locking nuts. Decoupling element in front exhaust pipe must not be bent more than 10°, otherwise it may be damaged.

Scheme 30

Scheme 30: Removing
Scheme 30: Removing

Scheme 31

Scheme 31
Scheme 31

Scheme 32

Scheme 32
Scheme 32

Scheme 33

Scheme 33
Scheme 33
  1. Remove intake air duct -1- to air filter (arrows).
  2. Remove the center engine cover (arrows).
  3. Remove cover -1- above the right cylinder head.
  4. Remove bolts (arrows).
  5. Remove air guide -1-.
  6. Remove air filter cover.
  7. Disconnect harness connector -3- from Mass Air Flow (MAF) sensor. see scheme 23
  8. Disengage EVAP canister valve -2- from air filter housing.
  9. Disconnect hose -1- from Secondary Air Injection (AIR) pump (turn toward left and pull off).
  10. Remove air guide hose from intake tube.
  11. Disconnect front right vacuum hose from engine.
  12. Remove bolt (arrow).. see scheme 23
  13. Remove air filter housing with Mass Air Flow (MAF) sensor and air guide hose.
  14. Disconnect electrical harness connectors -1- and -3- for oxygen sensors and expose the wires. NOTE: Secure a binding wire to connector for oxygen sensor behind catalytic converter to facilitate pulling in the wire during installation.
  15. Loosen upper bolt on connection of exhaust manifold / exhaust pipe.
  16. Loosen connecting bolts (arrows) at exhaust manifold / front exhaust pipe from below.
  17. Remove exhaust pipe from bracket (arrow). NOTE: Decoupling element in front exhaust pipe must not be bent more than 10°, otherwise it may be damaged.
  18. Loosen double clamps -1- and -2- of exhaust system and slide them toward rear.
  19. Pull front exhaust pipe at right slightly toward rear.
  20. Remove heat shield for drive shaft -arrows-.
  21. Unbolt driveshaft -1- from transmission and let it rest on heat shield -2-.
  22. Secure driveshaft using wire (arrow) at bracket -3- of fuel lines.
  23. Position Engine-/Gearbox Jack V.A.G 1383 A -Item B- with stand -Item A- under transmission and support transmission. NOTE: For vehicles with automatic transmission, support on transmission housing only and not on ATF pan of transmission.
  24. First remove bolts -1-, then bolts -2-.
  25. Slowly lower the rear subframe slightly using V.A.G 1383 A engine/transmission jack.
  26. Open all cable ties on transmission for wire connections of oxygen sensors behind catalytic converter.
  27. Expose cables.
  28. Carefully remove right exhaust pipe.

Installation is the reverse of removal, noting the following

Note. Wires of oxygen sensors must always be secured in the same position when installing so that contact with the exhaust pipe is avoided. After removing driveshaft, always remove any remaining locking fluid from thread bores in the transmission drive flange. Otherwise there is a possibility that the new bolts may get jammed when installed and shear when removed. Cleaning can be performed with a tap. Always replace driveshaft bolts (self-locking).

  1. Note the different tightening torques when securing the subframe.
  2. Use new bolts when securing.
  3. Tighten bolts -2- to 110 Nm and turn an additional 90°.
  4. Tighten bolts -1-. Note the different tightening methods for the various bolt versions. see scheme 33

Bolt versions

Scheme 34

Scheme 34
Scheme 34

Bolt -A- without ribbing.

Tightening torques: 25 Nm

Bolt -B- with ribbing.

Tightening torques: 75 Nm

Bolt -C- with screw head and washer ribbing.

Tightening torques: 30 Nm + turn another 90°.

  1. Align exhaust system free of tension. See «EXHAUST SYSTEM, ALIGNING FREE OF TENSION»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__exhaust-system-aligning-free-of-tension) .
ComponentNm
Driveshaft to transmission55
Heat shield for driveshaft to cover for Torsen differential25
Front exhaust pipe with catalytic converter to mounting strap25
Front exhaust pipe with catalytic converter to exhaust manifold25
Clamp for exhaust pipe40

TIGHTENING TORQUES: RIGHT FRONT EXHAUST PIPE WITH CATALYTIC CONVERTER

Exhaust system, aligning free of tension

To avoid noise and tension in the exhaust system, install exhaust system as follows

Note. Requirement for the installation of exhaust system is the exact alignment and tightening of front pipes and catalytic converters. Loosen all threaded connections of exhaust system (except exhaust manifold and flange connection, catalytic converter / intermediate pipe). Align exhaust system when cold. Following work procedure must be performed in the specified sequence. Dimensions provided in the illustrations are guiding dimensions.

  1. Vehicles without clamp between center and rear muffler

Note. Align exhaust system when cold.

Scheme 35

Scheme 35
Scheme 35
  1. Loosen double clamp mounting bolts. See item 4 .
  2. Slide exhaust system far enough toward front until end pipe -1- has distance -a- from bumper -2-. Dimension a = at least 40 mm
  3. Tighten screws of front clamps between catalytic converters and center muffler evenly to 40 Nm, installation position. See «INSTALLATION POSITION OF FRONT DOUBLE CLAMP»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__installation-position-of-front-double-clamp) . For correct distance of end pipes / bumper, adjust pre-tension on rear mount for rear muffler to -a- = 7 ... 11 mm.
  1. Vehicles with clamp between center and rear muffler

Note. Only for vehicles with double clamp between center and rear mufflers, the center muffler must also be aligned.

  1. Loosen double clamp mounting bolts at front. See item 4 and at rear see item 8 .
  2. Push exhaust system far enough forward (arrow) that the pretension at rear left retaining loop of center muffler is -a- = 7 ... 9 mm.
  3. Tighten screws of front clamps between catalytic converters and center muffler evenly to 40 Nm, installation position. See «INSTALLATION POSITION OF FRONT DOUBLE CLAMP»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__installation-position-of-front-double-clamp) .
  4. Slide rear muffler far enough toward front (arrow), until pre-tension at rear right retaining loop on rear muffler a = 7 to 11 mm.
  5. Tighten screws of rear clamp between main muffler and rear muffler evenly to 40 Nm, installation position. See «INSTALLATION POSITION OF FRONT DOUBLE CLAMP»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__installation-position-of-front-double-clamp) . Pre-tension of retaining loops is correct when distance -a- is set between end pipes -1- and bumper -2-. Dimension a = at least 40 mm

Installation position of front double clamp

  1. Screw tips must not project beyond the lower edge of the clamp.

Installation position of rear double clamp

  1. Screw tips must not project beyond the lower edge of the clamp.

Exhaust system, checking for proper seal

  1. Start engine and let run at idle.
  2. Seal tailpipes with cloths or plug for the duration of the leak test.
  3. Check for leaks by listening at connection areas of cylinder head/exhaust manifold, exhaust manifold/front exhaust pipe etc.
  4. Repair detected leaks.

Secondary air system

The Secondary Air Injection (AIR) system causes the catalytic converter to heat up more quickly, resulting in earlier operating readiness following cold start.

Principle

Due to over-enrichment of the mixture during the cold start phase, there is an increased amount of carbon monoxide in the exhaust. Secondary Air Injection (AIR) improves secondary oxidation in the catalytic converter and therefore reduces emissions. The heat produced by secondary oxidation greatly reduces start-up time for the catalytic converter, therefore improving exhaust quality during the cold start phase significantly.

Function

  1. In the cold start phase, the ECM -3- activates the Secondary Air Injection (AIR) pump -1- via the Secondary Air Injection (AIR) pump relay -2-. Air reaches the combination valves for Secondary Air Injection (AIR) -4- and -8-.
  2. The Secondary Air Injection (AIR) valve -5- is activated in parallel, which allows the vacuum to reach the combination valves for Secondary Air Injection (AIR) -4- and -8-. The appropriate combination valve for Secondary Air Injection (AIR) thereby opens the path for secondary air to the exhaust channels of the cylinder head.

Component overview

Note. The following list refers to see scheme 41.

  1. Secondary Air Injection (AIR) Pump Motor -V101- Component location. See «COMPONENT LOCATION OF SECONDARY AIR INJECTION (AIR) PUMP MOTOR -V101»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) . Checking. See «CHECK VOLTAGE SUPPLY OF THE SECONDARY AIR INJECTION (AIR) PUMP MOTOR»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
  2. Secondary Air Injection (AIR) pump relay -J299- Component location. See «COMPONENT LOCATION OF SECONDARY AIR INJECTION (AIR) PUMP RELAY -J299»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-location-of-secondary-air-injection) . Checking. See «SECONDARY AIR INJECTION (AIR) PUMP RELAY -J299- AND ACTIVATION, CHECKING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
  3. Combination valve for secondary air injection (right) Component location. See «COMBINATION VALVE FOR SECONDARY AIR INJECTION (AIR)»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__combination-valve-for-secondary-air-injection) . Checking. See «IGNITION COILS WITH POWER OUTPUT STAGES, CHECKING»(/audi/s6/c5-1999-2004/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
  4. Secondary Air Injection (AIR) solenoid valve -N112- Component location. See «COMPONENT LOCATION OF SECONDARY AIR INJECTION (AIR) SOLENOID VALVE -N112»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-location-of-secondary-air-injection) . Checking. See «SECONDARY AIR INJECTION (AIR) SOLENOID VALVE -N112- CHECKING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
  5. Check-valve Installation position: Arrow points in direction of aperture, as shown in figure.
  6. to Intake manifold
  7. Combination valve for secondary air injection (left) Component location. See «COMBINATION VALVE FOR SECONDARY AIR INJECTION (AIR)»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__combination-valve-for-secondary-air-injection) . Checking. See «IGNITION COILS WITH POWER OUTPUT STAGES, CHECKING»(/audi/s6/c5-1999-2004/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
  8. Vacuum reservoir Component location: Under wheel housing liner in front left wheel housing

Component location of Secondary Air Injection (AIR) Solenoid Valve -N112

  1. At rear on fuel rail pipe (arrow).

Scheme 36

Scheme 36
Scheme 36

Scheme 37

Scheme 37: Component location of Secondary Air Injection (AIR) Pump Motor -V101
Scheme 37: Component location of Secondary Air Injection (AIR) Pump Motor -V101
  1. At front right in engine compartment below the longmember (arrow)

Component location of Secondary Air Injection (AIR) Pump Relay -J299

  1. At position 2 in 3-pin relay carrier in E-box, plenum chamber

Combination valve for secondary air injection (AIR)

  1. at rear of cylinder heads

Note. The left combination valve for Secondary Air Injection (AIR) -2- is depicted in the illustration.

Scheme 38

Scheme 38
Scheme 38

Checking secondary air system for proper seal

  1. Check the connection pipes and hoses between Secondary Air Injection (AIR) pump motor and combination valves for proper seal. See «COMPONENT OVERVIEW»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-overview) .
  2. Check hoses and hose connections for secure seating.
  3. Check combination valves for Secondary Air Injection (AIR) system for proper seal. See «COMBINATION VALVES FOR SECONDARY AIR INJECTION (AIR) SYSTEM, CHECKING FUNCTION AND FOR PROPER SEAL»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

Final procedures

After repair work, the following work steps must be performed in the mentioned sequence

  1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
  2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
  3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.
  1. VAG1390 Hand Vacuum Pump

Test requirements

  1. No leaks in vacuum lines or hose connections.
  2. Vacuum lines not clogged.

Scheme 39

Scheme 39: Test sequence
Scheme 39: Test sequence
  1. Remove engine cover (arrows).
  2. Remove the air intake tube (arrows) between the air filter and the throttle valve part.
  3. Remove coolant reservoir -3- (arrows)
  4. Disconnect wire from Engine Coolant Level (ECL) Warning Switch -F66- and lay coolant reservoir to side. NOTE: Coolant hoses -1- and -2- remain connected.
  5. Disconnect vacuum hose -1- of combination valve to be checked -2-. NOTE: Left valve is displayed in illustration.
  6. Connect e.g. V.A.G 1390 hand vacuum pump to vacuum connection of combination valve to be checked.
  7. Loosen mounting parts -1- to -4- and remove noise insulation.
  8. Disconnect pressure hose -1- at Secondary Air Injection (AIR) pump motor and blow air in with light pressure (do not use pressurized air). NOTE: Disregard items -1- and -2- as well as arrows. Both combination valves must be closed, it must not be possible to blow through hose
  9. Operate hand vacuum pump. The respective combination valve must open, it must be possible to blow through

If the respective combination valve does not open

  1. Replace the combination valve.

After repair work, the following work steps must be performed in the mentioned sequence

  1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
  2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
  3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.
  1. VAG1526A hand multimeter
  2. V.A.G 1527 B Voltage Tester
  3. VAG1594A connector test kit
  4. VAG1598/31 test box
  1. Fuse for Secondary Air Injection (AIR) solenoid valve OK
  2. Fuel Pump (FP) Relay OK; checking. See «FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
  3. Ignition switched off.

Note. Voltage is supplied to Secondary Air Injection (AIR) Solenoid Valve -N112- via the Fuel Pump (FP) relay.

Work procedure

  1. Remove engine cover (arrows).

Checking internal resistance

  1. Disconnect harness connector from Secondary Air Injection (AIR) Solenoid Valve -N112- (arrow).
  2. Connect multimeter at valve for resistance measurement. Specified value: 25 to 35 ohms

If specified value is not obtained.

  1. Replace Secondary Air Injection (AIR) Solenoid Valve -N112-.

If specified value is obtained

Scheme 40

Scheme 40: Checking voltage supply
Scheme 40: Checking voltage supply
  1. Connect VAG1527B voltage tester as follows: SECONDARY AIR INJECTION SOLENOID VALVE CIRCUIT TEST: TERMINAL 1 Harness connector Terminal Measure to 1 Engine Ground (GND)
  2. Operate starter briefly. LED must light up.
  3. Switch ignition off.

If LED does not light up

  1. Check wire connection from harness connector terminal 1 to Fuel Pump (FP) Relay -J17- via fuse for open circuit according to wiring diagram. Specified value: Wire resistance max 1.5 ohm
  2. If necessary, repair wire connection.

If LED lights up

Scheme 41

Scheme 41: Checking control wire
Scheme 41: Checking control wire
  1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
  2. Check the following wire connection for open circuit according to wiring diagram: SECONDARY AIR INJECTION SOLENOID VALVE CIRCUIT TEST: TERMINAL 2 & TEST BOX SOCKET 44 Harness connector Terminal Test box Socket 2 44 Specified value: Wire resistance max 1.5 ohm
  3. Also check the wire for short circuit to B+ and Ground (GND). Specified value: infinity ohm (no continuity)
  4. If necessary, repair wire connection.

If no malfunctions are found in wire

  1. Replace Engine Control Module (ECM).

After repair work, the following work steps must be performed in the mentioned sequence

  1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
  2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
  3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.
  1. VAG1526A hand multimeter
  2. V.A.G 1527 B Voltage Tester
  3. VAG1594A connector test kit
  4. VAG1598/31 test box
  1. Battery voltage at least 12.7 V
  2. Fuse for secondary air pump -S130- (40 A) -item 4- in 3-pin relay carrier, E-box plenum chamber, OK
  3. Fuse S234 (in fuse holder, position 34) OK.
  4. Ignition switched off.

Test sequence

  1. Pull off rubber seal of plenum chamber cover in direction of arrow.
  2. Remove plenum chamber cover -1- toward front.
  3. Remove cover for E-box, plenum chamber (arrows).
  4. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
  5. Using wires e.g. from connector test kit V.A.G 1594 A, bridge terminals 1 and 46 on test box.
  6. Switch ignition on. Secondary Air Injection (AIR) Pump Relay -2- (in 3-pin relay carrier, E-box plenum chamber) must engage and Secondary Air Injection (AIR) Pump Motor -V101- must run.
  1. Secondary Air Injection (AIR) Pump Motor runs: Check voltage supply of the Secondary Air Injection (AIR) pump relay. See «CHECKING VOLTAGE SUPPLY OF SECONDARY AIR INJECTION (AIR) PUMP RELAY»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) . Check activation of the Secondary Air Injection (AIR) pump relay. See «CHECK ACTIVATION OF THE SECONDARY AIR INJECTION (AIR) PUMP RELAY»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
  2. Secondary Air Injection (AIR) Pump Motor does not run: Check voltage supply of the Secondary Air Injection (AIR) pump motor. See «CHECK VOLTAGE SUPPLY OF THE SECONDARY AIR INJECTION (AIR) PUMP MOTOR»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

Scheme 42

Scheme 42: Checking voltage supply of Secondary Air Injection (AIR) pump relay
Scheme 42: Checking voltage supply of Secondary Air Injection (AIR) pump relay
  1. Remove Secondary Air Injection (AIR) pump relay -2-.
  2. Connect multimeter for voltage measurement as follows. SECONDARY AIR INJECTION (AIR) PUMP RELAY CIRCUIT TEST: TERMINAL 8 3-pin relay carrier, E-box plenum chamber, position 3 Terminal Measure to 8 Engine Ground (GND) Specified value: approx. battery voltage

If specified value is not obtained

Scheme 43

Scheme 43
Scheme 43
  1. Check wire connection from battery + (terminal 30) via Fuse for secondary air pump -S130- to Secondary Air Injection (AIR) Pump Relay -J299- (in relay- and fuse-carrier in E-Box, plenum chamber, position 3) for open circuit according to wiring diagram. Specified value: Wire resistance max 1.5 ohm
  2. Connect multimeter for voltage measurement as follows. SECONDARY AIR INJECTION (AIR) PUMP RELAY CIRCUIT TEST: TERMINAL 4 3-pin relay carrier, E-box plenum chamber, position 3 Terminal Measure to 4 Engine Ground (GND)
  3. Operate starter briefly. Specified value: approx. battery voltage
  4. Switch ignition off.

If specified value is not obtained

  1. Check wire connection from Secondary Air Injection (AIR) Pump Relay -J299- (in 3-pin relay carrier, E-box plenum chamber) to Fuel Pump (FP) relay via Fuse -S234- (in fuse holder, position 34) for open circuit according to wiring diagram. Specified value: Wire resistance max 1.5 ohm

Scheme 44

Scheme 44: Check activation of the Secondary Air Injection (AIR) pump relay
Scheme 44: Check activation of the Secondary Air Injection (AIR) pump relay

Scheme 45

Scheme 45
Scheme 45
  1. Remove Secondary Air Injection (AIR) pump relay -2-.
  2. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
  3. Check the following wire connection for open circuit according to wiring diagram: SECONDARY AIR INJECTION (AIR) PUMP RELAY CIRCUIT TEST: TERMINAL 6 & TEST BOX SOCKET 46 3-pin relay carrier, E-box plenum chamber, position 3 Terminal Test box Socket 6 46 Specified value: Wire resistance max 1.5 ohm
  4. Also check the wire for short circuit to B+ and Ground (GND). Specified value: infinity ohm (no continuity)

If no malfunctions are detected

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

Scheme 46

Scheme 46: Check voltage supply of the Secondary Air Injection (AIR) pump motor
Scheme 46: Check voltage supply of the Secondary Air Injection (AIR) pump motor
  1. Loosen mounting parts -1- to -4- and remove noise insulation.
  2. Disconnect electrical harness connector -3- at Secondary Air Injection (AIR) Pump Motor -V101-. NOTE: Disregard items -1- and -2- as well as arrows.
  3. Connect VAG1527B voltage tester between terminals 1 and 2
  4. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
  5. Bridge terminals 1 and 46 at test box using wires e.g. from V.A.G 1594 A adapter test kit. LED must light up.

If LED does not light up

  1. Check wire connection from terminal 2 of harness connector to Secondary Air Injection (AIR) Pump Relay -J299- (in relay carrier in E-Box, plenum chamber, position 3) for open circuit according to wiring diagram.
  2. Check wire connection from terminal 1 of harness connector to Ground (GND) for open circuit according to wiring diagram. Specified value: Wire resistance max 1.5 ohm

If no malfunctions are detected

  1. Replace Secondary Air Injection (AIR) pump motor -V101-.

After repair work, the following work steps must be performed in the mentioned sequence

  1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
  2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
  3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

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