•

September 2013

Multiport Fuel Injection – 4.0L CEUC
Fastener Tightening Specifications

Intake air temperature sensor-to-Intake manifold
Intake manifold runner position sensor-to-Intake manifold
Intake manifold-to-bracket for the fuel rail
Low Fuel Pressure Sensor-to-High Pressure Pump
Low pressure line bolt
Manifold Absolute Pressure (MAP) sensor-to-charge air
cooler housing
Oxygen sensor
Throttle valve control module-to-charge air cooler
housing
Union nut-to-high pressure pump 1)
1)
2)

Nm
2.5
9
3
9
9
25
9
9
20 plus an
additional 45°
(⅛ turn)
2.5
2.5
9
15
9
3
55
5
25

Coat the union nut threads with clean engine oil.
Replace fastener(s)

Audi A6/S6 Quick Reference Specification Book

•

September 2013

101

Engine –
4.0L CEUC

Component
Air guide-to-air guide
Air guide with turbocharger recirculation valve-to-throttle
valve control module
Bracket for the fuel rail-to-Intake manifold
Bracket for the low pressure line bolt
Charge air cooler temperature sensor-to-throttle valve
control module
Fuel pressure sensor 2-to-fuel rail 1)
Fuel supply hose bolt
High pressure line bolt
High pressure pump-to-camshaft housing 2)

Ignition – 4.0L CEUC
Technical Data
4.0L 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
8 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
1-5-4-8-6-3-7-2

Fastener Tightening Specifications
Component
Camshaft Position (CMP) sensor-to-engine
Engine Speed (RPM) sensor-to-cylinder head
Ignition coil-to-cylinder head
Knock Sensor (KS)-to-engine
Wiring harness-to-cylinder head

102

Audi A6/S6 Quick Reference Specification Book

Nm
9
9
9
25
5

•

September 2013

Engine Mechanical – 3.0L CPNB
(TDI)
General, Technical Data

The engine number (“engine code” and “serial number”) is
located on the left side in the front under the high pressure
pump toothed belt (Æ). In addition, a sticker with “engine code”
and “serial number” is affixed to the intake manifold. Engine
codes beginning with C are four-digit. The first 3 digits of the
engine code indicate the displacement and the mechanical
structure of the engine. The fourth digit describes the engine
output and torque. The four digit engine code is on the type
plate, vehicle data label and engine control module.

Audi A6/S6 Quick Reference Specification Book

•

September 2013

103

Engine –
3.0L TDI CPNB

Engine Number Location

Engine Data
Code letters
Displacement
liter
Output
kW at RPM
Torque
Nm at RPM
Bore
diameter mm
Stroke
mm
Compression ratio
CZ
at least
Ignition sequence
Exhaust Gas Recirculation (EGR)
Turbocharger
Charge air cooler
Oxygen Sensor (O2S) regulation
Particulate Filter
Selective Catalytic Reduction (SCR)
- catalytic converter
Valve per cylinder

104

CPNB
2.967
176 @ 4000 to 4500
580 @ 1700 to 2750
83.0
91.4
16.8
51
1-4-3-6-2-5
Yes
1 Turbocharger
Yes
Heated Oxygen Sensor (HO2S) 1
Yes
Yes

Audi A6/S6 Quick Reference Specification Book

4

•

September 2013

Engine Assembly – 3.0L CPNB (TDI)
Fastener Tightening Specifications
Bolts and nuts

Engine mount to engine support bolt 1)

Fastener
size
M6
M7
M8
M10
M12
-

Engine support bolt
Heat shield to engine support bolt
Retaining plate bolt
Subframe to retaining plate bolt
Transverse beam to lock carrier nut
Stop for torque bracket to transverse beam
bolt
Torque bracket bolt 1)

1)

-

Nm
9
15
20
40
65
90 plus an
additional 90°
(¼ turn)
40
10
20
55
40
30
20 plus an
additional 90°
(¼ turn)

Replace fastener(s).

Audi A6/S6 Quick Reference Specification Book

•

September 2013

105

Engine –
3.0L TDI CPNB

Component

Crankshaft, Cylinder Block – 3.0L CPNB
(TDI)
Allocation of Crankshaft Bearing
Shells for Cylinder Block

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.
Allocation of bearing shells to cylinder block is identified
with a letter by each bearing. -Arrow-: belt pulley side.
Letter on guide frame
R
G
B

106

Color of bearing
Red
Yellow
Blue

Audi A6/S6 Quick Reference Specification Book

•

September 2013

Engine –
3.0L TDI CPNB

Allocation of Crankshaft Bearing
Shells for Guide Frame

Bearing shells with the correct thickness are allocated to the
guide frame at the factory. Colored dots on the sides of the
bearing shells identify the bearing shell thickness. Allocation of
the bearing shells to the guide frame is marked on the flywheel
flange of the crankshaft by a row of letters. The first letter
represents bearing 1, the second letter is for bearing 2, etc.
Letter on guide frame
R
G
B

Audi A6/S6 Quick Reference Specification Book

Color of bearing
Red
Yellow
Blue

•

September 2013

107

Fastener Tightening Specifications
Component
Bracket for A/C compressor tighten in 2 steps:
- Diagonally
- Diagonally
Bracket for generator tighten in 2 steps:
- Diagonally
- Diagonally
Connecting rod bearing cap to connecting rod bolt 1)

Nm
5
40
5
40
35 plus an
additional 90°
(¼ turn)
9
60 plus an
additional 90°
(¼ turn)
23
9
50 plus an
additional 90°
(¼ turn)
20 plus an
additional 90°
(¼ turn)

Cover for the belt pulley side sealing flange bolt
Drive plate to crankshaft bolt 1
Idler roller for the ribbed belt to engine bolt
Oil temperature sensor 2 bolt
Tensioner for the ribbed belt bolt 1)
Washer to vibration damper bolt 1)

1)

Replace fastener(s).

108

Audi A6/S6 Quick Reference Specification Book

•

September 2013

Engine –
3.0L TDI CPNB

Ribbed Belt Sealing Flange Tightening Specification

Tighten the bolts in 11 steps in the sequence shown.
Steps 1 … 3:
Steps
1

Bolts

2
3

1
2, 3, 4

Tightening Specification
Attach the sealing flange with the
seal to the cylinder block
Tighten for the idler roller 23 Nm
Tighten the M6x20 to 9 Nm

Audi A6/S6 Quick Reference Specification Book

•

September 2013

109

Ribbed Belt Sealing Flange Tightening
Specification (cont'd)

Steps 4 … 8:

110

Steps
4

Bolts

5
6
7

10
1 to 19
1 to 19

8

1 to 19

Tightening Specification
Insert a temperature regulator for
the engine oil cooler with the cover
Install all the way in by hand.
3 Nm
3 Nm - this measurement accounts
for the seal shrinkage
Tighten 90° additional turn

Audi A6/S6 Quick Reference Specification Book

•

September 2013

Engine –
3.0L TDI CPNB

Ribbed Belt Sealing Flange Tightening
Specification (cont'd)

Steps 9 … 11:
Steps
9
10

Bolts
2, 3, 4
2, 3, 4

11

2, 3, 4

Tightening Specification
Remove the steel bolts M6x20
Insert the aluminum bolts and
tighten to 3 Nm
Turn the aluminum bolts 90° further

Audi A6/S6 Quick Reference Specification Book

•

September 2013

111

Guide Frame Tightening Specifications

Step
1
2
3
1)

Component
Tighten bolts 1 through 16 in sequence 1)
Tighten bolts 1 through 16 in sequence
Tighten bolts 1 through 16 in sequence

Nm
30
50
an additional
180° (½ turn)

Replace fastener(s).

112

Audi A6/S6 Quick Reference Specification Book

•

September 2013

Crankshaft Dimensions
Honing dimension in
mm

Crankshaft bearing
pin diameter

Basic dimension

65.000

Crankshaft
connecting rod
journal diameter
60.000
– 0.022
– 0.042

– 0.022
– 0.042

Piston Ring End Gaps
Piston ring dimensions
in mm
1st compression ring
2nd compression ring
Oil scraping ring
1)

New

Wear limit

0.25 to 0.40
0.70 to 0.90
0.25 to 0.50

0.60
1.20
0.70

Not determined.

Piston ring dimensions
in mm
1st compression ring
2nd compression ring
Oil scraping ring

New

Wear limit

0.009 to 0.130
0.05 to 0.09
0.03 to 0.07

0.160
0.11
0.10

Piston and Cylinder Dimensions
Honing dimension in
mm
Nominal dimension
Repair stage
1)

Piston diameter

Cylinder bore
diameter
83.006 and 83.014 1)
83.046 and 83.054 1)

82.924 and 82.936 1)
82.964 and 82.976 1)

Dimension without graphite coating (thickness 0.02 mm). The graphite coating
wears away.

Piston Projection, Measuring at “TDC”
Piston Projection above the Upper Edge of the