Engine –
3.0L CGXC, CTUB

Fuel Supply – 3.0L CGXC, CTUB
Fastener Tightening Specifications
Component
Accelerator pedal module to pedal bracket
Air filter housing to bracket
Bracket for fuel tank pressure sensor
Bracket to the fuel tank
Carrier plate
Evaporative Emission (EVAP) canister
Fuel filler neck bolt
Fuel filler neck nut
Fuel pump control module nut
Fuel tank
Fuel tank leak detection control module nut
Heat shield for fuel tank
Locking flange cover to floor
Locking ring to fuel tank
Securing strap

Nm
8
4
4
23
23
20
23
2.5
1.6
23
1.6
23
1.5
120
23

Turbocharger, G-Charger – 3.0L CGXC,
CTUB
Fastener Tightening Specifications
Component
Bleeder screw for the left charge air cooler
Bracket for change-over valves-to-supercharger
Charge air cooler-to-supercharger housing 1)
Charge air pressure sensor-to-supercharger 1)
Drive head-to-supercharger housing 1)
Engine lifting eye-to-supercharger
Insulation plate-to-supercharger
Nut-to-threaded pin
Threaded pin-to-engine
1)

Nm
1.5 to 3.0
9
10
10
25
27
5
20
17

Replace fastener(s).

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

73

Exhaust System, Emission Controls – 3.0L
CGXC, CTUB
Fastener Tightening Specifications
Component
Bonded rubber bushing bracket for secondary air
injection pump motor nut
Bracket for secondary air injection pump motor-to-body
Catalytic converter-to-manifold nut 1, 2
Front clamping sleeve nut
Front muffler-to-catalytic converter nut 1, 2
Hose from the secondary air injection pump motor-toright secondary air injection combination valve
Right secondary air injection combination valve-to-engine
Secondary air combination valve heat shield
Suspended mount-to-center muffler
Suspended mount-to-front muffle
Left secondary air injection combination valve-to-engine
1)
2)

Nm
9
9
20
23
20
9
9
9
23
23
9

Replace fastener(s).
Coat the thread with hot bolt paste.

74

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

Step
1
2
3
1)
2)

Component
Tighten bolts 1 through 9 in sequence 1) 2)
Tighten bolts 1 through 9 in sequence
Tighten bolts 1 through 9 in sequence

Engine –
3.0L CGXC, CTUB

Left Exhaust Manifold Tightening Specifications

Nm
Hand-tighten
15
25

Replace fastener(s).
Coat the thread on the nut with hot bolt paste. For the correct hot bolt paste, refer to
the Electronic Parts Catalog (ETKA).

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

75

Right Exhaust Manifold Tightening Specifications

Step

1)
2)

Component

Nm
Hand-tighten

1

Tighten bolts 1 through 9 in sequence 1) 2)

2

Tighten bolts 1 through 9 in sequence

15

3

Tighten bolts 1 through 9 in sequence

25

Replace fastener(s).
Coat the thread on the nut with hot bolt paste. For the correct hot bolt paste, refer to
the Electronic Parts Catalog (ETKA).

76

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

Technical Data
Engine data
Idle speed
Fuel pressure before high pressure
pump
Fuel pressure after high pressure
pump

4.2L/4V/273 kW-Motor
Cannot be adjusted, it is regulated
by idle stabilization
3 to 6 bar pressure
30 to 125 bar pressure

Fastener Tightening Specifications
Component
Adapter-to-air filter housing upper section
Air guide-to-air filter housing
Air filter housing upper section-to-lower section
Bracket for high pressure line-to-cylinder head
Camshaft position sensor-to-housing
Fuel line union nut
Fuel pressure sensor
High pressure line threaded connection-to-fuel rail
High pressure line-to-bracket
High pressure line-to-high pressure pump
Housing-to-protective plate
- Threaded pin
- Nut
Intake manifold lower section 1)
Intake manifold runner position sensor 2-to-vacuum
actuator
Low fuel pressure sensor-to-high pressure pump
Oxygen sensor
Throttle valve control module 1)
1)

Nm
1.5
1.5
2.5
9
9
25
22
40
9
25
9
9
9
2.5
15
55
10

Tighten bolts in a diagonal sequence.

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

77

Engine –
3.0L CGXC, CTUB

Multiport Fuel Injection – 3.0L CGXC,
CTUB

Control Valve Control Module
Tightening Specification

Step
1
2
3

78

Component
Tighten bolts 5 and 6
Tighten bolt 6
Tighten bolt 5

Nm
Hand-tighten
10
10

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

Step
1
2

Component
Tighten bolts (Æ)
Tighten bolts (Æ)

Engine –
3.0L CGXC, CTUB

High Pressure Pump Tightening Specifications

Nm
Hand-tighten
In steps to 20 Nm

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

79

Ignition System – 3.0L CGXC, CTUB
Ignition Tightening Specifications
Component
Camshaft Position (CMP) sensor
Knock Sensors (KS)
Wiring for ignition coils at cylinder head cover

Nm
9
25
5

Technical Data
Test data
Engine idle speed
Ignition timing
Ignition/glow plug system

Spark plugs

Names
Removing
and
installing
Ignition sequence

80

3.0L TFSI Engine
Cannot be adjusted, it is regulated by idle
stabilization
Not adjustable; regulated by the Engine Control
Module (ECM).
Single coil ignition system with 8 ignition coils
(output stages integrated) that are connected
directly to the spark plugs via the ignition
cables.
Refer to Electronic Parts Catalog (ETKA).
Maintenance Procedures Rep. Gr.03
1-4-3-6-2-5

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

Engine Mechanical – 4.0L
CEUA, CGTA
General, Technical Data

Engine –
4.0L CEUA, CGTA

Engine Number Location

The engine number -arrow B- is visible, if the housing for the charge
air cooler is removed. The first 3 digits of the engine code -arrow
A- are visible, when the engine cover is removed. The 4-digit engine
code is on the type plate, vehicle data label and ECM.

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

81

Engine Data
Code letters
Displacement
Output
Torque

CEUA
3.999
309 @ 6000
600 @ 1500 to
4500
Bore
diameter mm
84.5
Stroke
mm
89.0
Compression ratio
10.1
RON
at least
98 1)
Fuel injection and ignition system
Bosch Motronic
Ignition sequence
1-5-4-8-6-3-7-2
Turbocharger
2 turbocharger
Oxygen Sensor (O2S) regulation
2 sensors
before catalytic
converter
2 sensors after
cat.converter
Variable valve timing
Intake
Exhaust
Variable intake manifold
Yes
Secondary Air Injection (AIR) system
Yes
Valve per cylinder
4
1)

liter
kW at RPM
Nm at RPM

CGTA
3.999
381 @ 6000
650 @ 1500 to
4500
84.5
89.0
10.1
98 1)
Bosch Motronic
1-5-4-8-6-3-7-2
2 turbocharger
2 sensors
before catalytic
converter
2 sensors after
cat. converter
Intake
Exhaust
Yes
Yes
4

Unleaded RON 95 is also permitted but performance is reduced.

Engine Assembly – 4.0L CEUA, CGTA
Fastener Tightening Specifications
Component
Bolts and nuts

Engine bracket
Engine mount-to-engine support 1)
Engine support
Heat shield
Subframe
Wheel housing bracket bolt
1)

Fastener
size
M6
M7
M8
M10
M12
-

Nm
9
15
20
40
65
20
90 plus an
additional 90°
(¼ turn)
40
10
55
9

Replace fastener(s).

82

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

Crankshaft, Cylinder Block – 4.0L CEUA,
CGTA

Engine –
4.0L CEUA, CGTA

Allocation of Crankshaft Bearing Shells
for Cylinder Block – New Crankshaft

Bearing shells with the correct thickness are allocated to the
cylinder block in the factory. Colored dots on the sides of the
bearing shells identify the bearing shell thickness. The allocation
of the bearing shells to the cylinder block is marked by one letter
each at the front left on cylinder block as shown in the illustration.
Letter on cylinder block
R
S
G
U
B

Color of bearing
Red
Black
Yellow
Green
Blue

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

83

Allocation of Crankshaft Bearing
Shells for Guide Frame

Bearing shells with the correct thickness are allocated to the
guide frame in the factory. Colored dots on the sides of the
bearing shells identify the bearing shell thickness. The allocation
of bearing shells to the guide frame is identified by a letter
on the front crankshaft flange as shown in the illustration.
Letter on cylinder block
R
S
G
U
B
84

Color of bearing
Red
Black
Yellow
Green
Blue

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

Engine –
4.0L CEUA, CGTA

Allocation of Crankshaft Bearing Shells for Guide
Frame – Used and Reworked Crankshafts

Bearing shells are allocated to cylinder block corresponding to
the color markings stamped into the cylinder block. With used
and reworked crankshafts, measure the crankshaft pivot pins to
allocate the appropriate bearing shells. Thicker oversized bearing
shells are available for a reworked crankshaft. These have the
same color markings as the original size bearing shells.
Letter on cylinder block
R
S
G
U
B

Color of bearing
Red
Black
Yellow
Green
Blue

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

85

Fastener Tightening Specifications
Component
Drive plate-to-crankshaft 1)
Connecting rod bearing cap-to-connecting rod 1)
Idler roller for the ribbed belt
Oil spray jet for piston cooling 3)
Ribbed belt tensioning element
1)
2)

3)

2)

Nm
60 plus an
additional 90°
(¼ turn)
50 plus an
additional 90°
(¼ turn)
22
9
22
55

Replace fastener(s).
For bolt tightening clarification, refer to ElsaWeb, Ribbed Belt Drive Overview, items
1 and 2.
Insert bolts with locking compound

Spur Gear Unit Tightening Specifications

Step
1

86

Component

Nm

Tighten bolts 1 to 5 in a diagonal sequence