AUDI BNS — 4.2L Engine
4.2L · 420 hp
Engine overview
Manufacturer
AUDI
Displacement
4.2 L
Power
420 hp
Production years
2006-2009
Fuel type
Petrol
Vehicles with this engine
8E
8H
Torque figures by job
From the step-by-step procedures for this engine — each figure sits in the step that uses it.
- 20 Nm (15 lb-ft) — Tighten base plates for support elements to
- 20 Nm (15 lb-ft) — Tighten base plates for support elements to
- 25 Nm (18 lb-ft) — Fit camshaft clamps T40070 to both cylinder heads and tighten bolts (arrows) to
- 20 Nm (15 lb-ft) — Screw locking pin3242 into bore (tightening torque
- 40 Nm (30 lb-ft) — Have a 2nd mechanic apply a torque of
- 60 Nm (44 lb-ft) — Pre-tighten bolt (1) on inlet camshaft to
- 60 Nm (44 lb-ft) — Pre-tighten bolt (2) on exhaust camshaft to
- 20 Nm (15 lb-ft) — Screw the locking pin3242 into the hole (
Removing and installing sump (top section)
- 5 Nm (3.7 lb-ft) — Fit sump (top section), paying attention to dowel sleeves , and tighten bolts (1
- 25 Nm (18 lb-ft) — Fit camshaft clamps T40070 to both cylinder heads and tighten bolts (arrows) to
- 20 Nm (15 lb-ft) — Screw locking pin3242 into bore (tightening torque
- 40 Nm (30 lb-ft) — Tension camshaft adjuster by applying a torque of
- 20 Nm (15 lb-ft) — Screw the locking pin3242 into the hole (
Removing and installing camshafts
- 25 Nm (18 lb-ft) — Tighten bolts for camshaft clamp T40070 to
- 20 Nm (15 lb-ft) — Screw locking pin3242 into bore (tightening torque
- 20 Nm (15 lb-ft) — Tighten base plates for support elements to
Removing and installing sump (bottom section)
- 5 Nm (3.7 lb-ft) — Tighten all bolts to an initial torque of
- 9 Nm (6.6 lb-ft) — Tighten all bolts to
Stress-free alignment of exhaust system
- 23 Nm (17 lb-ft) — Tighten bolts on clamps evenly to
- 23 Nm (17 lb-ft) — Tighten bolts on front clamps evenly to
- 23 Nm (17 lb-ft) — Tighten bolts on rear clamps evenly to
- 23 Nm (17 lb-ft) — Tighten bolts to
Removing and installing exhaust manifold (left-side)
- 20 Nm (15 lb-ft) — Pre-tighten nuts in the sequence (1
- 30 Nm (22 lb-ft) — Tighten nuts in the sequence (1
Factory specifications
Values from the manufacturer documentation for this engine.
Engine (general)
| Engine code | BNS |
| Capacity | 4163 cc |
| Idle speed | 720 - 840 rpm |
| Normal | 10.0 - 14.0 bar |
| Minimum | 9.0 bar |
| Differential limit between cylinders | < 3.0 bar |
| Oil pressure | 1.5 > bar/rpm |
| Oil pressure | 3.5 > / 2000 bar/rpm |
Engine (petrol)
| Fuel system (make and type) | Bosch Motronic ME 7.1.1 |
| Number of cylinders | 8 |
| Firing order | 1 - 5 - 4 - 8 - 6 - 3 - 7 - 2 |
| Fuel pump pressure | > 6.0 bar |
| Fuel pump pressure | 18.0 - 120.0 bar |
| Injector resistance | 13 - 16 ohms |
| Lambda | 0.97 – 1.03 |
| CO at fast-idle speed | < 0.3 % |
Cooling system
| Cap pressure | 1.4 - 1.6 bar |
| Thermostat opens at | 87 °C |
| Thermostat fully open at | 102 °C |
Capacities
| Manual transmission | 0A3 |
| Gearbox refill | 3.2 l |
| Differential, 4WD front | 1.1 l |
| Differential, 4WD rear | 0.9 l |
| Transfer box | 0.55 l |
| Cooling system | 12.0 l |
| Air-conditioner refrigerant | 440 ± 20 g |
| Air-conditioner compressor oil | 130 ± 10 ml |
Torque settings
| Cylinder head bolts — Stage 1 | 30 Nm |
| Cylinder head bolts — Stage 2 | 60 Nm |
| Cylinder head bolts — Stage 3 | 90 ° |
| Cylinder head bolts — Stage 4 | 90 ° |
| Manual transmission filler plug | 40 Nm |
| Spark plugs | 30 Nm |
| Oxygen sensor | 55 Nm |
| Front hub | M14: 115 Nm + 180° M16: 200 Nm + 180° |
| Rear hub | 200 Nm + 180° |
| Wheel bolts | 120 Nm |
Emissions
| Emission code | 70/220*2002/80B |
| Emission standard | Euro 4 |
| CO2 average | 322 - 334 g/km |
| CO | 0.284 - 0.354 g/km |
| HC | 0.068 - 0.083 g/km |
| NOx | 0.026 - 0.045 g/km |
| Emission code | 70/220*2003/76B |
| CO2 average | 334 g/km |
| CO | 0.354 g/km |
| HC | 0.068 g/km |
| NOx | 0.045 g/km |
| CO2 average | 324 g/km |
| CO | 0.284 g/km |
| HC | 0.083 g/km |
| NOx | 0.026 g/km |
Engine codes in the same family
The same code prefix usually means the same block with a different output, fuel or model year. Procedures are often shared — check the code on the engine plate.
Workshop procedures for this engine
Step-by-step procedures from the workshop database, carrying 48 torque figures.
- Removing and installing timing chain cover (bottom) · 7 torque figures
- Removing and installing high-pressure pump · 8 torque figures
- Removing timing chains from camshafts - vehicles from 03.2007 onwards · 6 torque figures
- Removing and installing drive chain for auxiliary drives · 7 torque figures
- Removing and installing exhaust manifold (right-side) · 6 torque figures
- Removing timing chains from camshafts - vehicles up to 03.2007 · 4 torque figures
- Removing and installing exhaust manifold (left-side) · 4 torque figures
- 8-cylinder direct petrol injection engine (4.2 ltr. 4-valve RS 4), mechanics — Removing engine · 1 torque figures
- Removing and installing oil filter housing
- 8-cylinder direct petrol injection engine (4.2 ltr. 4-valve RS 4), mechanics — Installing engine · 1 torque figures
- Removing and installing coolant pipe (right-side) · 1 torque figures
- Removing and installing mounting for torque reaction support
- Removing and installing continued coolant circulation pump V51
- Removing and installing front exhaust pipe (left-side) with starter catalytic converter and main catalytic converter
- Removing and installing coolant pipe (left-side)
- Removing and installing suction-jet pump in left fuel tank chamber
- Removing and installing engine mountings
- Removing and installing timing chain covers (left and right)
- Removing and installing front exhaust pipe (right-side) with starter catalytic converter and main catalytic converter
- Removing and installing air cleaner housing · 1 torque figures
- Removing and installing spur gear drive
- 8-cylinder direct petrol injection engine (4.2 ltr. 4-valve RS 4), mechanics — Separating engine and gearbox · 1 torque figures
- Removing and installing auxiliary radiator (right-side) · 1 torque figures
- Removing and installing fuel pump control unit J538
- Removing and installing camshaft timing chains - vehicles up to 03.2007
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The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.
Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.
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The story behind TorqFix →Workshop data on this page last updated 22 Aug 2026.