Engine specifications (Audi A4 B6)

Warning: Individual characteristics are also given in the text of the Chapter and, if their implementation is mandatory, are highlighted in bold.

Characteristic	Meaning
Gasoline engines	In-line 4-cylinder and V-shaped 6-cylinder, aluminum, water-cooled, DOHC type (1.6 L OHC), timing belt drive, microprocessor control, thermometric air mass meter and turbocharger on 1.8T models
Diesel engines	Inline 4-cylinder (OHC) and V-shaped 6-cylinder (DOHC) with water cooling, timing belt drive and turbocharger

Engine designation//Start of production

Characteristic	Meaning
1.6	ALZ//from 11/00
1.8T	AVJ//from 11/00 to 07/02
1.8T	BFB//from 07/02
1.8T	-//from 11/02
2.0	ALT//from 11/00
2.0FSI	AWA//from 07/02
2.4	BDV//from 09/01
3.0	ASN//from 11/00
S4 4.2	BBK//from 03/03
1.9TDI	AVB//from 05/01
1.9TDI	AWX, AVF//from 11/00
2.5TDI	AYM, BCZ//from 08/01 to 07/02
2.5TDI	BDG//from 07/02
2.5TDI	AKE, BAU, BDH//from 11/00

Nominal power, kW/hp. (at rpm)

Characteristic	Meaning
ALZ	75//102 (5600)
AVJ	110//150 (5700)
BFB	120//163 (5700)
BFB	140//190 (5700)
ALT	96//130 (5700)
AWA	110//150 (6000)
BDV	125//170 (6000)
ASN	162//220 (6300)
BBK	253//344 (7000)
AVB	74//100 (4000)
AWX, AVF	96//130 (4000)
AYM, BCZ	114//155 (4000)
BDG	120//163 (4000)
AKE, BAU, BDH	132//180 (4000)

Nominal torque, Nm, at rpm

Characteristic	Meaning
ALZ	148/3600
AVJ	210/1750
BFB	225/1950
BFB	240/1950
ALT	195/3300
AWA	200/3250
BDV	230/3200
ASN	300/3200
BBK	410/3500
AVB	250/1900
AWX	285/1750
AVF	310/1900
AYM, BCZ	310/1500
BDG	310/1400
AKE, BAU, BDH	370/1500

Number and arrangement of cylinders/valves per cylinder/type

Characteristic	Meaning
1.6	4, in-line / 2 / OHC
1.8, 2.0	4, in-line / 5 / DOHC
2.0FSI	4, in-line / 4 / DOHC
2.4, 3.0	6, V-shaped / 5 / DOHC
S4 4.2	8, V-shaped / 5 / DOHC
1.9TDI	4, in-line / 2 / OHC
2.5TDI	6, V-shaped / 4 / DOHC

Cylinder firing order

Characteristic	Meaning
4-cylinder	1-3-4-2
V6	1-4-3-6-2-5
V8	1-5-4-8-6-3-7-2

Cylinder displacement, cm³ // Cylinder diameter x Piston stroke

Characteristic	Meaning
1.6	1596 // 81.0 x 77.4
1.8T	1781 // 81.0 x 86.4
2.0	1984 // 82.5 x 92.8
2.4	2393 // 81.0 x 77.4
3.0	2976 // 82.5 x 92.8
4.2	4163 // 84.5 x 92.8
1.9TDI	1896 // 79.5 x 95.5
2.5TDI	2496 // 78.3 x 86.4

Compression ratio

Characteristic	Meaning
1.6, 2.0	10.3
1.8T	9.3
2.0FSI	11.5
2.4, 3.0	10.5
S4 4.2	11.0
1.9TDI, 2.5TDI (AYM, BCZ, BDG, AKE)	18.5
2.5TDI (BAU, BDH)	19.5

Compression pressure

Characteristic	Meaning
1.6, 2.0 l	10.0 — 13.0
wear limit	7.0
1.8 l	9.0 — 14.0
wear limit	7.5
3.0, 4.2 l	10.0 — 14.0
wear limit	9.0
1.9L TDI	25.0 — 31.0
wear limit	19.0
2.5L TDI	24.0 — 33.0
wear limit	24.0

Oil pressure switch sensor

Response pressure, atm/body color

Characteristic	Meaning
Petrol engines	1.4±0.2/black
Diesel engines 1.9 l	0.7±0.15/brown
Diesel engines 2.5 l	0.9±0.15/gray

Oil pressure control values at 80°C

Characteristic	Meaning
Engines 1.6 and 2.0 l	2 atm. at idle speed. 2.7 – 4.5 atm. at 2000 rpm
Engine 1.8 l	1.3 atm. at idle speed. 3.5 – 4.5 atm. at 2000 rpm
Engine 3.0 l	1.8 atm. at idle speed. 4.0 atm. at 2000 rpm
Engine 4.2 l	2.0 atm. at idle speed. 3.5 atm. at 3500 rpm
TDI engines 1.9 and 2.5 l	0.8 atm. at idle speed. 2.0 atm. at 2000 rpm

Tightening force of threaded connections, Nm

Tightening torques for fasteners are also given in the text of the Chapter and in some illustrations*.

* Tightening torques highlighted in bold in the text must be strictly observed; efforts not shown in bold are only approximate.

Characteristic	Meaning
Cylinder head mounting bolts
Engine 1.6, 1.8, 2.0 and 3.0 l
1 reception	20
2nd reception	40
3rd reception	at an angle of 90°
4th reception	at an angle of 90°
Engine 2.4 l
1 reception	40
2nd reception	60
3rd reception	at an angle of 90°
4th reception	at an angle of 90°
Engine 4.2 l
1 reception	30
2nd reception	60
3rd reception	at an angle of 90°
4th reception	at an angle of 90°
Diesel engine 1.9 l
1 reception	40
2nd reception	60
3rd reception	at an angle of 90°
4th reception	at an angle of 90°
Diesel engine 2.5 l
1 reception	35
2nd reception	60
3rd reception	at an angle of 90°
4th reception	at an angle of 90°
Crankshaft main bearing cap fastening bolts
Engines 1.6, 1.8, 2.0 l	65Nm +90°
2.4L engines
horizontal	25
vertical	65Nm+90°
3.0L Engines	35Nm+90°
Diesel engines 1.9 l	65Nm+90°
Diesel engines 2.5 l	60Nm+90°
Connecting rod bearing cap fastening bolts	30Nm +90°
Oil pump to cylinder block
Engines 1.6, 1.8 l	15
2.0L Engines	15Nm+90°
2.4L engines	25
3.0L Engines	35Nm+90°
Diesel engines 1.9 l	16
Diesel engines 2.5 l	22
Oil pan bolts
Engines 1.6, 1.8, 2.0, 3.0 l
M6	10
M7	15
M8	22
M10	45
2.4L engines	10
Diesel engines	15
Oil pan drain plug
Engines 1.6 l	50
Engines 1.8, 2.0, 2.4, 3.0 l	30
Diesel engines 1.9 l	30
Diesel engines 2.5 l	25
Oil pressure switch sensor
Petrol engines	25
Diesel engines	20
*Flywheel (drive disk)*
Bolt 22.0/22.5 mm	60Nm+90°
Bolt 35/42/43 mm (dual mass flywheel)	60Nm+180°
Crankshaft pulley/damper
Engines 1.6, 1.8, 2.0 l	90Nm+90°
Engines 2.4, 3.0 l	200Nm+180°
Diesel engines 1.9 l	120Nm+90°
Diesel engines 2.5 l	200Nm+180°
Clutch basket to flywheel	25 (22 on front-wheel drive models with 2.4, 3.0 l engines)
*Camshaft sprocket*
Engine 1.6 l	100
Engines 1.8, 2.0 l	65
Engine 2.4 l	55
Engine 3.0 l	100
Diesel engines 1.9 l
Central bolt	100
Side bolts	25
Diesel engines 2.5 l
Central bolt	75
Side bolts	22
Camshaft bed
Engines 1.6, 2.0 l	20
Engines 1.8, 2.4, 3.0 l	10
Diesel engines 1.9 l	8Nm+90°
Diesel engines 2.5 l	15
*Camshaft cover*
Petrol engines	10
Diesel engines 1.9 l	9
Diesel engines 2.5 l	10
*Intake manifold to cylinder head*
Engines 1.6, 2.0 l	20
Engines 1.8, 2.4, 3.0, 4.2 l	10
Diesel engines 1.9 l	25
Diesel engines 2.5 l	10
*Exhaust manifold to cylinder head*
Petrol engines	25
Diesel engines 1.9 l	25
Diesel engines 2.5 l	22
*Intake pipe to manifold*
Engines 1.6, 1.8, 2.0 l	40
Engines 2.4, 3.0 l	25
Diesel engines	21
*Water pump*
Engines 1.6, 1.8, 2.0, 3.0 l	15
2.4L engines	10
Diesel engines 2.5 l	10
*Fuel distribution line to intake manifold*	10
*Injector clamp*
Diesel engines 1.9 l	12Nm+270°
Diesel engines 2.5 l	30
Union nut of the injector pipeline	30
*Fuel injection pump gear*
Diesel engines 2.5 l	22
*Oil pressure switch sensor*
Engines 1.6, 1.8, 2.4, 3.0 l	25
2.0L Engines	20
Diesel engines 2.5 l	25
*Camshaft position sensor*
Engine 1.6 l	13
*Lambda probe*
Engines 1.6, 1.8, 2.0, 3.0 l	50
2.4L engines	55
*Knock sensor*
Petrol engines	20
*Oil filter*
Diesel engines 2.5 l	25

Additionally

Characteristic	Meaning
*Engine 1.8 l*
Intake manifold supports to intake manifold and holder	20
Turbocharger to exhaust manifold. Be sure to replace the bolts. Lubricate the threads and bearing surfaces of the bolt heads with high-temperature paste, such as AUDI G 052 112 A3.	35
Turbocharger holder to cylinder block	25
Turbocharger Holder to Turbocharger	30
Air Duct Hose Clamps	3.5
*Engine 3.0 l*
Coolant pipe rear to cylinder head	10
Combination valve to cylinder head	10
Rear timing belt cover to cylinder head and also to cylinder block	10 (replace)
Guide roller holder to cylinder head	10 (replace)
Coolant pipe front to cylinder head
M6	10
M8	23
Power steering high pressure line to pump	47
Power steering high pressure line to cylinder head	10
Power steering high pressure line to rear coolant pipe	20
*Engine 4.2 l*
Chain tensioner to cylinder head	5Nm + 90°
Cylinder head cover (sequence: center bolt, 2 bolts from the end, the remaining 12 bolts crosswise from the inside out)	10
Fuel supply to the fuel distribution line	25
*Diesel engine 1.9 l*
Hall sensor to cylinder head (with gripping compound)	10
Hub to camshaft	100
Oil supply line to the oil filter holder	25
Turbocharger oil return line (bolts, strength class 10.9)	15
Upper Coolant Pipe to Eyelet	20
Wheel bolts	120