63

Fuel Supply – 3.0L CTUA
Fastener Tightening Specifications
Component
Accelerator pedal module
Air filter housing nut
Carrier plate
Evaporative Emission (EVAP) canister 2)

Nm
8
8
20
1.5
20
20
20
3.5
20
1.6
20
1.5
2
1.5
110

Exhaust system suspended mount
Fuel filler neck bolt
Fuel filler tube protective plate 1)
Fuel pump control module
Fuel tank
Fuel tank leak detection control module to EVAP canister
Heat shield lock washer
Locking flange cover
Locking ring
1)

2)

For bolt tightening clarification, refer to ElsaWeb, Fuel Tank with Attachments
Overview, items 8 and 9.
For bolt tightening clarification, refer to ElsaWeb, EVAP System Overview, items 2,
3 and 14.

Turbocharger, G-Charger – 3.0L CTUA
Fastener Tightening Specifications
Component
Bleeder screw
Changeover valves bracket
Charge air cooler to supercharger bolt 1)
Charge air pressure sensor (replace)
Drive head 1)
Engine lifting eye
Insulation plate
Left Charge Air Cooler (CAC) 1)
Right Charge Air Cooler (CAC) 1)
Supercharger nut
Supercharger threaded pin
1)

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

Replace fastener(s).

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September 2013

Fastener Tightening Specifications
Component
Bonded rubber bushing nut
Catalytic converter nut
Catalytic converter to manifold nut 3)
Front clamping sleeve nut
Heat shield
Left Secondary Air Injection (AIR) combination valve
Rear clamping sleeve nut
Right Secondary Air Injection (AIR) combination valve
Secondary Air Injection (AIR) pump motor hose-to-right
Secondary Air Injection (AIR) combination valve
Secondary Air Injection (AIR) pump motor bracket
Suspended mount 1) 2)
1)
2)

3)

Nm
9
23
23
23
10
9
23
9
9
9
20
23

Replace fastener(s).
For bolt tightening clarification, refer to ElsaWeb, Muffler Overview see items -2, 14
and 19-.
Coat the thread with hot bolt paste.

Audi A6/S6 Quick Reference Specification Book

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September 2013

65

Engine –
3.0L CTUA

Exhaust System, Emission Controls – 3.0L
CTUA

Left Exhaust Manifold Tightening Specifications

Step

1)
2)

Component

Nm
Hand-tighten

1

Tighten bolts 1 through 9 in sequence

2

Tighten bolts 1 through 9 in sequence

15

3

Tighten bolts 1 through 9 in sequence

25

1) 2)

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).

66

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September 2013

Engine –
3.0L CTUA

Right Exhaust Manifold Tightening Specifications

Step

1)
2)

Component

Nm
Hand-tighten

1

Tighten bolts 1 through 9 in sequence

2

Tighten bolts 1 through 9 in sequence

15

3

Tighten bolts 1 through 9 in sequence

25

1) 2)

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 A6/S6 Quick Reference Specification Book

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September 2013

67

Multiport Fuel Injection – 3.0L CTUA
Technical Data
3.0L TFSI engine
Engine idle speed
Fuel pressure before high pressure
pump
Fuel pressure after high pressure
pump

Cannot be adjusted, it is regulated
by idle stabilization
3.0 to 6.0 Bar pressure
30 to 125 Bar pressure

Fastener Tightening Specifications
Component
Air duct
Camshaft Position (CMP) sensor
Fuel pressure sensor 1)
Fuel rail bracket 2)
High-pressure line 3)
High Pressure Pump

Nm
1.5
9
22
2.5
25
Hand-tighten
20
10

Intake Air Temperature (IAT) sensor (G42)/Manifold
Absolute Pressure (MAP) sensor (G71)
Intake manifold runner position sensor 2
Low fuel pressure sensor
Oxygen Sensor (O2S)
High-pressure line bracket
High-pressure line protective plate nut
High-pressure line protective plate threaded pin
High-pressure line threaded connection
Threaded connection-to-high pressure pump
Throttle Valve Control Module 4)
1)
2)

3)
4)

2.5
15
55
9
9
9
40
27
10

Oil the threads.
For bolt tightening clarification, ElsaWeb, Intake Manifold Lower Section, Fuel Rail
and Fuel Injector Overview, items 10, 11 and 12.
Coat the threads on the union nut with fuel.
In a diagonal sequence

68

Audi A6/S6 Quick Reference Specification Book

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September 2013

Engine –
3.0L CTUA

Lower Intake Manifold Tightening Specifications

Component
Tighten bolts and nuts (Æ) diagonally in stages

Audi A6/S6 Quick Reference Specification Book

Nm
9

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September 2013

69

Control Valve Control Module
Tightening Specifications

Step
1
2
3

70

Bolts
5, 6
6
5

Nm
Hand-tighten
10
10

Audi A6/S6 Quick Reference Specification Book

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September 2013

Technical Data
3.0L TFSI engine
Engine idle speed
Ignition timing
Ignition/glow plug system

Spark plugs

Names
Tightening
specifications

Ignition sequence

Cannot be adjusted, it is regulated
by idle stabilization.
Not adjustable, regulated by the
Engine Control Module (ECM).
Single coil ignition system with
6 ignition coils (output stages
integrated) that are connected
directly to spark plugs via the ignition
cables.
Refer to data sheets for exhaust
emission test.
Maintenance Procedures Rep. Gr.
03
1-4-3-6-2-5

Fastener Tightening Specifications
Component
Camshaft Position (CMP) sensor
Engine Speed (RPM) sensor
Knock Sensor (KS)
Wiring harness

Audi A6/S6 Quick Reference Specification Book

Nm
9
9
25
5

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September 2013

71

Engine –
3.0L CTUA

Ignition – 3.0L CTUA

Engine Mechanical – 4.0L CEUC
General, Technical Data
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 engine serial
number (“engine code“ and “serial number“) is located on the front of
the cylinder block on the left side -arrow B-. The first 3 digits of the
engine code stand for displacement and the mechanical structure
of the engine. They are stamped in the cylinder block, including
the serial number. The fourth digit describes the engine output
and torque and depends on the Engine Control Module (ECM).

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1)

Unleaded RON 95 is also permitted but performance is reduced.

Audi A6/S6 Quick Reference Specification Book

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September 2013

73

Engine –
4.0L CEUC

Engine Data
Code letters
CEUC
Displacement
liter
3.999
Output
kW at RPM
309 @ 5000 to 6400
Torque
Nm at RPM
550 @ 1400 to 5200
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
Exhaust Gas Recirculation (EGR)
No
Turbocharger, Supercharger
2 turbocharger
Knock control
4 sensors
Charge air cooler
Yes
Oxygen Sensor (O2S) regulation
2 sensors before catalytic converter
2 sensors after catalytic converter
Variable valve timing
Intake / Exhaust
Variable intake manifold
Yes
Secondary Air Injection (AIR) system
Yes
Valve per cylinder
4

Engine Assembly – 4.0L CEUC
Fastener Tightening Specifications
Component
Bolts and nuts

Engine bracket-to-engine
Engine mount-to-engine support 1)
Engine support-to-engine
Subframe mount sensor and subframe
mount actuator to engine mount bolt
Subframe-to-engine bracket
1)

Fastener
size
M6
M7
M8
M10
M12
-

Nm

-

9
15
20
40
65
20
90 plus an
additional 90°
(¼ turn)
60
6

-

55

Replace fastener(s).

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September 2013

Crankshaft, Cylinder Block – 4.0L CEUC

Engine –
4.0L CEUC

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 sides of bearing
shells serve for identifying bearing shell thickness. The allocation
of bearing shells to guide frame is identified by a letter on the
front crankshaft flange, as shown in the illustration. The letter
series begins with crankshaft bearing “5“ (transmission side)
and ends with crankshaft bearing “1“ (belt pulley side).
Letter on guide frame
R
S
G
U
B
Audi A6/S6 Quick Reference Specification Book

Color of bearing
Red
Black
Yellow
Green
Blue
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September 2013

75

Allocation of Crankshaft Bearing
Shells for Guide Frame

Bearing shells with the correct thickness are allocated to the cylinder
block in the factory. Colored dots on sides of bearing shells serve
for identifying bearing shell thickness. Allocation of bearing shells to
cylinder block is marked by one letter each at left front on cylinder
block (can be read from outside) as shown in the illustration.
Letter on guide frame
R
S
G
U
B

76

Color of bearing
Red