Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
4.2L - Fuel Injection & Ignition, Engine Code(S): BFM
2004 Audi A8SECTION 4.2L - Fuel Injection & Ignition, Engine Code(S): BFM
- 24 Multiport Fuel Injection (MFI)
- Motronic injection system, servicing
- Safety precautions
- Rules for cleanliness
- Technical data
- Component locations overview
- Notes
- Relay carrier in passenger's footwell
- Relay and fuse carrier at right of rear compartment
- Relay carrier in electronics box in plenum chamber
- MIL exhaust emissions warning lamp
- EPC warning lamp
- Connector assignment
- Electronics box in plenum chamber
- Connector console (underside of transmission)
- Knock sensor connectors
- Front view
- Secondary air injection valve
- Secondary air injection pump motor (below right longitudinal member)
- Fuel pressure regulator and holding pressure, checking
- Injection rate, leakage and spray pattern of injectors, checking
- Wiring and component check with test box V.A.G 1598/31
- Engine Control Module (ECM) -J623-, replacing
- Intake manifold, removing and installing
- Oxygen sensor before catalytic converter, removing and installing
- Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131-, removing and installing
- Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130-, removing and installing
- Motronic injection system, servicing
- 28 Ignition/Glow plug system
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.