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.
Oil check valves, replacing
2004 Audi A8SECTION Oil check valves, replacing
NOTE:
- If irregular valve noise occurs repeatedly during short journeys and disappears after extended driving, the oil check valves must be replaced.
Removing
- Remove intake manifold → 24 MULTIPORT FUEL INJECTION (MFI) .
- Remove crankcase ventilation pipes - 1 - and - 2 -.
- Remove cover - 3 - below intake manifold.
- Remove oil check valves - 1 - and - 2 -.
Installing
Installation is in reverse order of removal, note the following:
NOTE:
- Replace gaskets and O-rings.
- Secure all hose connections using hose clamps of series-production status
- Install intake manifold → 24 MULTIPORT FUEL INJECTION (MFI) .
Torque specifications
| Component | Nm |
| Oil check valve to cylinder block | 20 |
| Cover to cylinder block | 10 |
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.