Audi 2003 A8 Instruction manual

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
Workshop Manual
Audi A8 2003 ➤
8-cylinder TDI engine (4.2 ltr. 4-valve common rail),
mechanics
Engine ID BVN BMC
Edition 12.2013
Service
Service Department. Technical Information

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
List of Workshop Manual Repair GroupsList of Workshop Manual
Repair GroupsList of Workshop Manual Repair Groups
Repair Group
00 - Technical data
10 - Removing and installing engine
13 - Crankshaft group
15 - Cylinder head, valve gear
17 - Lubrication
19 - Cooling
21 - Turbocharging/supercharging
26 - Exhaust system
Technical information should always be available to the foremen and mechanics, because their
careful and constant adherence to the instructions is essential to ensure vehicle road-worthiness and
safety. In addition, the normal basic safety precautions for working on motor vehicles must, as a
matter of course, be observed.
Service
All rights reserved.
No reproduction without prior agreement from publisher.
Copyright © 2014 Audi AG, Ingolstadt A0051122920

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
Contents
00 - Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1 Engine number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 Engine data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
3 Safety precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3.1 Safety precautions when working on the fuel supply system . . . . . . . . . . . . . . . . . . . . . . . . 3
3.2 Safety precautions when using testers and measuring instruments during a road test . . . . 4
3.3 Safety precautions when working on the cooling system . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4 General repair instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1 Rules for cleanliness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.2 Checking for leaks in the fuel system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.3 Foreign particles in engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.4 Contact corrosion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.5 Routing and attachment of pipes, hoses and wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.6 Installing radiators, condensers and charge air coolers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.7 Checking vacuum system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
10 - Removing and installing engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1 Removing engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2 Separating engine and gearbox . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3 Securing engine to assembly stand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4 Installing engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
5 Assembly mountings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
5.1 Assembly mountings - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
5.2 Removing and installing engine mounting (left-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
5.3 Removing and installing engine mounting (right-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
5.4 Removing and installing mounting for torque reaction support . . . . . . . . . . . . . . . . . . . . . . 48
13 - Crankshaft group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
1 Lowering subframe for repair and assembly work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
2 Servicing work on pulley end . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
2.1 Poly V-belt drive - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
2.2 Removing and installing poly V-belt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
2.3 Removing and installing tensioner for poly V-belt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
2.4 Removing and installing vibration damper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
2.5 Oil seal and sealing flange (pulley end) - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . 64
2.6 Renewing crankshaft oil seal (pulley end) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
2.7 Removing and installing sealing flange (front) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
3 Servicing work on timing chain end . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
3.1 Drive plate - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
3.2 Removing and installing drive plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
3.3 Renewing crankshaft oil seal (timing chain end) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
3.4 Renewing oil seal for toothed belt drive sprocket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
3.5 Vacuum pump - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
3.6 Removing and installing vacuum pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
4 Removing and installing crankshaft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
4.1 Crankshaft - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
4.2 Allocation of main bearing shells for new crankshafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
4.3 Allocation of crankshaft bearing shells for retaining frame without visible colour coding . . 95
4.4 Crankshaft dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
4.5 Measuring axial clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
4.6 Measuring radial clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Audi A8 2003 ➤
8-cylinder TDI engine (4.2 ltr. 4-valve common rail), mechanics - Edition 12.2013
Contents i

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
5 Dismantling and assembling pistons and conrods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
5.1 Pistons and conrods - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
5.2 Removing and installing pistons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
5.3 Piston and cylinder dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
5.4 Measuring radial clearance of conrods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
5.5 Allocation of conrod bearing shells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
5.6 Measuring piston projection at TDC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
15 - Cylinder head, valve gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
1 Chain drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
1.1 Timing chain covers - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
1.2 Removing and installing timing chain covers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
1.3 Camshaft timing chains - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
1.4 Detaching camshaft timing chains from camshafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
1.5 Removing and installing camshaft timing chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
1.6 Drive chain for valve gear - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
1.7 Removing and installing drive chain for valve gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
1.8 Chain for auxiliary drives - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
1.9 Removing and installing chain for auxiliary drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
1.10 Auxiliary drives - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
1.11 Renewing oil seal for power steering pump drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
1.12 Removing and installing spur gear drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
2 Removing and installing cylinder head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
2.1 Cylinder head - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
2.2 Cylinder head cover - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
2.3 Removing and installing cylinder head cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
2.4 Removing and installing cylinder head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
2.5 Checking compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
3 Servicing valve gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
3.1 Valve gear - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
3.2 Measuring axial clearance of camshafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
3.3 Measuring radial clearance of camshafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
3.4 Removing and installing camshafts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
3.5 Renewing valve stem oil seals with cylinder head installed . . . . . . . . . . . . . . . . . . . . . . . . 173
3.6 Renewing valve stem oil seals with cylinder head removed . . . . . . . . . . . . . . . . . . . . . . . . 176
3.7 Checking hydraulic valve compensation elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
3.8 Valve dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
3.9 Machining valve seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
3.10 Checking valve guides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
3.11 Checking valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
17 - Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
1 Removing and installing parts of lubrication system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
1.1 Oil pump, sump (bottom section), sump (centre section) - exploded view . . . . . . . . . . . . . . 182
1.2 Removing and installing oil level and oil temperature sender G266 . . . . . . . . . . . . . . . . . . 184
1.3 Removing and installing sump (bottom section) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
1.4 Removing and installing sump (centre section) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186
1.5 Removing and installing oil pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
1.6 Sump (top section) - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
1.7 Removing and installing sump (top section) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
1.8 Oil cooler, pressure control valve, oil filter housing and spray nozzle valve - exploded view
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
1.9 Removing and installing oil cooler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
1.10 Removing and installing oil filter housing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
1.11 Removing and installing pressure control valve for crankcase breather system . . . . . . . . 206
Audi A8 2003 ➤
8-cylinder TDI engine (4.2 ltr. 4-valve common rail), mechanics - Edition 12.2013
ii Contents

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
1.12 Removing and installing mounting plate for oil cooler, pressure control valve and oil filter
housing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
1.13 Removing and installing oil pressure switch F1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
1.14 Removing and installing oil temperature sender G8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
1.15 Checking oil pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
1.16 Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212
1.17 Checking engine oil level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212
19 - Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
1 Removing and installing parts of cooling system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
1.1 Connection diagram - coolant hoses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
1.2 Draining and filling cooling system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
1.3 Coolant pump and thermostat - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
1.4 Removing and installing coolant pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
1.5 Removing and installing thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
1.6 Checking thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
1.7 Removing and installing coolant pipes (front) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
1.8 Removing and installing coolant pipe (left-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
1.9 Removing and installing coolant pipe (right-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
1.10 Removing and installing coolant pipe (rear) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
1.11 Removing and installing coolant temperature sender G62 . . . . . . . . . . . . . . . . . . . . . . . . 240
1.12 Radiator and radiator fans - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
1.13 Removing and installing radiator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
1.14 Removing and installing radiator cowl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
1.15 Removing and installing radiator fans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
1.16 Checking cooling system for leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
21 - Turbocharging/supercharging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
1 Servicing charge air system with turbocharger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
1.1 Turbocharger - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
1.2 Removing and installing turbocharger (left-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
1.3 Removing and installing turbocharger (right-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
1.4 Charge air cooling - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266
1.5 Removing and installing charge air cooler (left-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268
1.6 Removing and installing charge pressure sender G31 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
1.7 Removing and installing charge air cooler (right-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
26 - Exhaust system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
1 Removing and installing parts of exhaust system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
1.1 Exhaust system - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
1.2 Emission control - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
1.3 Removing and installing exhaust gas temperature sender 1 G235 . . . . . . . . . . . . . . . . . . 280
1.4 Removing and installing exhaust gas temperature sender 1 for bank 2 G236 . . . . . . . . . . 281
1.5 Removing and installing exhaust gas temperature sender 2 G448 . . . . . . . . . . . . . . . . . . 282
1.6 Removing and installing exhaust gas temperature sender 2 for bank 2 G449 . . . . . . . . . . 284
1.7 Removing and installing temperature sender 2 before particulate filter G498 . . . . . . . . . . 288
1.8 Removing and installing temperature sender before particulate filter G506 . . . . . . . . . . . . 291
1.9 Separating Y-pipe and rear silencers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
1.10 Removing and installing starter catalytic converter (left-side) . . . . . . . . . . . . . . . . . . . . . . 295
1.11 Removing and installing starter catalytic converter (right-side) . . . . . . . . . . . . . . . . . . . . . . 301
1.12 Removing and installing exhaust pipe (left-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
1.13 Removing and installing exhaust pipe (right-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
1.14 Removing and installing particulate filter/main catalytic converter (left-side) . . . . . . . . . . . . 309
1.15 Removing and installing particulate filter/main catalytic converter (right-side) . . . . . . . . . . 310
1.16 Exhaust manifold - exploded view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
1.17 Removing and installing exhaust manifold (left-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312
Audi A8 2003 ➤
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Contents iii

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1.18 Removing and installing exhaust manifold (right-side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312
1.19 Stress-free alignment of exhaust system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313
1.20 Aligning tailpipes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
1.21 Checking exhaust system for leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
2 Servicing exhaust gas recirculation system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 316
2.1 Exhaust gas recirculation on cylinder bank (left-side) - exploded view . . . . . . . . . . . . . . . . 316
2.2 Removing and installing exhaust gas recirculation control motor 2 V339 (left-side) . . . . . . 317
2.3 Exhaust gas recirculation on cylinder bank (right-side) - exploded view . . . . . . . . . . . . . . 317
2.4 Removing and installing control motor for exhaust gas recirculation V338 (right-side) . . . . 319
2.5 Exhaust gas recirculation cooler with change-over flap - exploded view . . . . . . . . . . . . . . 319
2.6 Removing and installing exhaust gas recirculation cooler with change-over flap . . . . . . . . 320
2.7 Removing and installing exhaust gas recirculation cooler . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Audi A8 2003 ➤
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iv Contents

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00 – Technical data
1 Engine number
(ARL003637; Edition 12.2013)
♦ The engine number (including “engine code” and “serial num‐
ber”) can be found on the inner part of the block below the
intake manifold (left-side).
♦ There is also a sticker on the intake manifold showing the “en‐
gine code” and “serial number”.
♦ The engine code is also included on the vehicle data sticker.
Audi A8 2003 ➤
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1. Engine number 1

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2 Engine data
Code letters BMC BVN
Capacity ltr. 4.134 4.134
Power output kW at rpm 235/3750 240/3750
Torque Nm at rpm 650/1800 … 25
00
650/1800 … 25
00
Bore ∅ mm 83.0 83.0
Stroke mm 95.5 95.5
Compression ratio 16.4 16.4
Fuel According to DIN EN 590 DIN EN 590
Firing order 1-5-4-8-6-3-7-2 1-5-4-8-6-3-7-2
Exhaust gas recirculation yes yes
Turbocharging/supercharg‐
ing
yes yes
Catalytic converter yes yes
Charge air cooling yes yes
Lambda probes before cat‐
alytic converter
yes yes
Particulate filter yes yes
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2 Rep. gr.00 - Technical data

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3 Safety precautions
⇒ “3.1 Safety precautions when working on the fuel supply sys‐
tem”, page 3
⇒ “3.2 Safety precautions when using testers and measuring in‐
struments during a road test”, page 4
⇒ “3.3 Safety precautions when working on the cooling system”,
page 4
3.1 Safety precautions when working on the
fuel supply system
When working on the fuel system note the following warnings:
WARNING
Risk of injury - fuel system operates under pressure.
♦ Wrap a clean cloth around the connection before opening
the fuel system. Then release pressure by carefully loos‐
ening the connection.
♦ Wear protective gloves.
♦ Wear safety goggles.
The fuel can become extremely hot. This can cause injuries.
♦ In extreme cases the temperature of the fuel lines and the
fuel can be up to 100 °C after the engine is switched off.
Allow the fuel to cool down before disconnecting the lines
- danger of scalding.
♦ Wear protective gloves.
♦ Wear safety goggles.
Caution
The high-pressure pump has very close tolerances and must
not be allowed to run without fuel. To prevent this and to enable
the engine to start quickly after parts have been renewed, it is
important to observe the following:
♦ If the high-pressure pump or the components of the fuel
system between the fuel tank and the high-pressure pump
are removed or renewed, the fuel system must be bled ⇒
Rep. gr. 23 ; Bleeding fuel system after installing high-
pressure pump .
Observe the following points to prevent personal injuries and
damage to the injection and glow plug system:
♦ Persons wearing a cardiac pacemaker must at all times main‐
tain a safe distance from high-voltage components such as
injectors and gas-discharge headlights.
♦ Always switch off the ignition before connecting or discon‐
necting tester cables or electrical wiring for the injection or
glow plug system.
♦ Do not open any fuel line connections while the engine is run‐
ning.
♦ Always switch off ignition before washing engine.
Audi A8 2003 ➤
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3. Safety precautions 3

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♦ Erase any entries in event memory resulting from repairs
⇒ Vehicle diagnostic tester.
Caution
To prevent irreparable damage to the electronic components
when disconnecting the battery:
♦ Observe notes on procedure for disconnecting the battery.
♦ Always switch off the ignition before disconnecting the
battery ⇒ Electrical system; Rep. gr. 27 .
3.2 Safety precautions when using testers
and measuring instruments during a
road test
Note the following if testers and measuring instruments have to
be used during a road test:
WARNING
Accidents can be caused if the driver is distracted by test
equipment while road-testing, or if test equipment is not prop‐
erly secured.
Persons sitting in the front passenger's seat could be injured if
the airbag is triggered in an accident.
• The use of test equipment while driving causes distraction.
• There is an increased risk of injury if test equipment is not
secured.
♦ Test equipment must always be secured on the rear seat
with a strap and operated from the rear seat by a second
person.
3.3 Safety precautions when working on the
cooling system
When working on the cooling system note the following warnings:
WARNING
Hot steam/hot coolant can escape - risk of scalding.
♦ The cooling system is under pressure when the engine is
hot.
♦ To allow pressure to dissipate, cover filler cap on coolant
expansion tank with cloth and open carefully.
Caution
Overheating can occur if the filler cap is not fitted properly.
♦ The filler cap must engage positively and audibly when it
is closed.
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4 Rep. gr.00 - Technical data

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4 General repair instructions
⇒ “4.1 Rules for cleanliness”, page 5
⇒ “4.2 Checking for leaks in the fuel system”, page 5
⇒ “4.3 Foreign particles in engine”, page 6
⇒ “4.4 Contact corrosion”, page 6
⇒ “4.5 Routing and attachment of pipes, hoses and wiring”, page
6
⇒ “4.6 Installing radiators, condensers and charge air coolers”,
page 6
⇒ “4.7 Checking vacuum system”, page 6
4.1 Rules for cleanliness
Even small amounts of dirt can cause malfunctions. For this rea‐
son, please observe the following rules when working on the fuel
supply system, injection system and turbocharger:
♦ Carefully clean connection points and the surrounding area
with engine cleaner or brake cleaner and dry thoroughly before
opening.
♦ Immediately seal open lines and connections with clean plugs,
for example from engine bung set - VAS 6122- .
♦ Do not remove sealing caps from components until immedi‐
ately prior to installation. Keep components that are to be re-
used in new, sealable plastic bags.
♦ Place parts that have been removed on a clean surface and
cover them over. Do not use fluffy cloths.
♦ Carefully cover or seal open components if repairs cannot be
carried out immediately.
♦ Only install clean components; replacement parts should only
be unpacked immediately prior to installation. Do not use parts
that have not been stored in the proper packaging (e.g. in tool
boxes etc.).
♦ When the system is open: Do not work with compressed air.
Do not move the vehicle unless absolutely necessary.
♦ Make sure that no fuel runs onto the fuel hoses. Should this
occur, the fuel hoses must be cleaned again immediately.
♦ Also ensure that no diesel fuel comes into contact with the
coolant hoses. Should this occur, the hoses must be cleaned
immediately. Damaged hoses must be renewed.
♦ Protect unplugged electrical connectors against dirt and mois‐
ture and make sure connections are dry when attaching.
4.2 Checking for leaks in the fuel system
– Start the engine and let it run at medium speed for a few mi‐
nutes.
– Switch off ignition.
– Check the entire fuel system for leaks.
– If leaks are found although the connections have been tight‐
ened to the correct torque, the relevant component must be
renewed.
– Then carry out a test drive with at least one full-power accel‐
eration.
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4. General repair instructions 5

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– Then check high-pressure part of fuel system again for leak‐
age.
4.3 Foreign particles in engine
♦ When performing assembly work on the engine, all open pas‐
sages in the intake and exhaust systems must be sealed with
suitable plugs (e.g. from engine bung set - VAS 6122- ) to
prevent foreign particles from entering the engine.
♦ In the event of mechanical damage to one of the cylinder
banks, the intake and exhaust systems and combustion cham‐
bers of the opposite cylinder bank must always be examined
to prevent further damage occurring later.
Note
If the turbocharger has suffered mechanical damage
⇒ page 252
4.4 Contact corrosion
Contact corrosion can occur if unsuitable fasteners are used (e.g.
bolts, nuts, washers, etc.).
For this reason, only fasteners with a special surface coating are
used.
Additionally, all rubber and plastic parts and all adhesives are
made of non-conductive materials.
Always install new parts if you are not sure whether used parts
can be re-fitted ⇒ Electronic parts catalogue .
Note the following:
♦ We recommend using only genuine replacement parts; these
have been tested and are compatible with aluminium.
♦ We recommend the use of Audi accessories.
♦ Damage caused by contact corrosion is not covered under
warranty.
4.5 Routing and attachment of pipes, hoses
and wiring
♦ Mark fuel lines, hydraulic lines, vacuum lines and electrical
wiring etc. before removal so they can be re-installed in the
original positions and correctly connected. Make sketches or
take photographs if necessary.
♦ To prevent damaging pipes, hoses and wiring, ensure suffi‐
cient clearance from all moving or hot components in engine
compartment (little space in engine compartment).
4.6 Installing radiators, condensers and
charge air coolers
Even when the radiator, condenser and charge air cooler are cor‐
rectly installed, slight impressions may be visible on the fins of
these components. This does not mean that the components are
damaged. If the fins are only very slightly distorted, this does not
justify renewal of the radiator, charge air cooler or condenser.
4.7 Checking vacuum system
Special tools and workshop equipment required
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6 Rep. gr.00 - Technical data

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♦ Hand vacuum pump - VAS 6213-
Procedure
– Check all vacuum lines in the complete vacuum system for:
♦ Cracks
♦ Traces of animal bites
♦ Kinked or crushed lines
♦ Lines porous or leaking
– Check vacuum line to solenoid valve and from solenoid valve
to corresponding component.
– If a fault is stored in the memory, check the vacuum lines lead‐
ing to the corresponding component and also check the re‐
maining vacuum lines in the system.
– If it is not possible to build up pressure with hand vacuum pump
- VAS 6213- or if the pressure drops again immediately, check
hand vacuum pump and connecting hoses for leaks.
Audi A8 2003 ➤
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4. General repair instructions 7

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10 – Removing and installing engine
1 Removing engine
Special tools and workshop
equipment required
♦ Removal lever - 80 - 200-
♦ Eye-head bolt - 3368-
♦ Used oil collection and ex‐
traction unit - V.A.G 1782-
or -VAS 6622A-
♦ Engine bung set - VAS
6122-
♦ Scissor-type assembly
platform - VAS 6131 A- with
support set for Audi - VAS
6131/10-
♦ Drip tray for workshop hoist
- VAS 6208-
♦ Spark plug connector pliers - V.A.G 1922-
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8 Rep. gr.10 - Removing and installing engine

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♦ Release tool - VAS 1978/8A- from wiring harness repair set -
VAS 1978 B-
♦ Tensioning strap - T10038-
♦ Tool set for wiper arms - T10369-
Procedure
Note
♦ The engine is removed from underneath together with the
gearbox and subframe (with lock carrier detached).
♦ All cable ties which are released or cut open when removing
must be fitted in the same position when installing.
– Discharge the refrigerant system ⇒ Air conditioner system -
with refrigerant R134a .
Caution
Observe notes on procedure for disconnecting the battery ⇒
Electrical system; Rep. gr. 27 .
– Switch off ignition.
Audi A8 2003 ➤
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1. Removing engine 9

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Note
♦ To make sure you can still move the front wheels when the
battery has been disconnected, only disconnect the battery
with the ignition key inserted.
♦ On four-wheel drive vehicles the electronic parking brake must
be released before disconnecting the battery, so that the prop‐
shaft can be turned during removal.
– Remove luggage compartment side trim cover (right-side)
-arrows-.
– Remove cover -1- over battery.
Note
Disregard -item 2-.
– Disconnect earth cable -arrow- at battery.
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10 Rep. gr.10 - Removing and installing engine

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– Carefully pull engine cover panel off four retaining pins one
after the other -arrows-.
– Remove cover above coolant expansion tank -arrows-.
WARNING
Hot steam or hot coolant can escape when expansion tank is
opened; cover filler cap with cloth and open carefully.
– Open filler cap on coolant expansion tank.
– Remove both front wheels.
– Release fasteners -1-, -2- and -4- and take off noise insulation
panels.
– Place drip tray for workshop hoist - VAS 6208- under engine.
– Remove drain plug -arrow- and let coolant drain.
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1. Removing engine 11

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– Disconnect coolant hose -arrow- from coolant pipe and drain
off remaining coolant.
– Remove air hose (front left) -arrows-.
– Pull off retaining clip for bottom coolant hose and detach cool‐
ant hose -1- from radiator.
Note
Disregard -item 2-.
– Remove front and rear sections of front wheel housing liners
(left and right) ⇒ Rep. gr. 66 .
– Remove bumper cover (front) ⇒ Rep. gr. 63 .
– Unscrew bolts -arrows- and detach top section of air cleaner
housing (left-side).
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12 Rep. gr.10 - Removing and installing engine

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– Remove bolts -arrows- and detach top section of air cleaner
housing (right-side).
– Unplug electrical connector -arrow- for headlights on both
sides.
– Pull off bonnet seal.
– Pull off retaining clip and remove top coolant hose -arrow- from
radiator.
Note
To prevent damage to the refrigerant lines, ensure that the pipes
and hoses are not stretched, kinked or bent.
– Remove refrigerant line from air conditioner compressor.
– Seal off open lines and connections with clean plugs from en‐
gine bung set - VAS 6122- .
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1. Removing engine 13

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– Remove oil filler neck on cylinder head cover (left-side). To do
so, lift tab -1- and turn oil filler neck clockwise -arrow-.
– Detach clamp -1- on reservoir.
– Detach refrigerant line -3- from reservoir.
– Unscrew bolts -2- and remove reservoir from lock carrier.
– Seal off open lines and connections with clean plugs from en‐
gine bung set - VAS 6122- .
– Fit oil filler neck on cylinder head cover (left-side).
– Unplug electrical connector -arrow- going to radiator fan 2 -
V177- .
– Unplug electrical connector (left and right) -arrow- at bonnet
lock and move wiring clear.
Audi A8 2003 ➤
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14 Rep. gr.10 - Removing and installing engine