2021 Audi Q8/S7/S5 Cylinder Head Oil Leak TSB

Owners of certain 2021 Audi models, including the Q8, S7, and S5, may experience an Audi Q8 cylinder head oil leak. This issue, detailed in Technical Service Bulletin (TSB) 2053278/9, specifically affects vehicles equipped with 2.9L and 3.0L TFSI engines. The TSB, released on July 14, 2023, supersedes an earlier bulletin, Group 15 number 21-39, dated June 25, 2021, to provide updated labor operations.

Symptoms

Owners might notice several signs indicating an Audi Q8 cylinder head oil leak:

• Oil loss in the area around the engine compartment, front end, and underbody. This can manifest as visible oil stains or drips under the vehicle.
• Oil level warning (too low). The vehicle's instrument cluster may display a warning indicating insufficient oil.
• There is a smell coming from the engine compartment. This is often described as a burning oil smell, particularly after driving.

Workshop findings have pinpointed leaks around the cylinder head cover, valve cover, cylinder head, injector, or the Audi valvelift system actuator.

Technical Background

The root cause of these oil leaks has been identified as metal shavings produced during the manufacturing process. These shavings can be present in the sealing groove between the cylinder head cover and the cylinder head, compromising the seal and leading to leaks. Audi has implemented improved production processes to address this issue in newer vehicles.

Diagnosis and Trigger Conditions

To accurately diagnose the source of the oil leak, technicians follow a specific procedure. The initial step involves removing engine covers and noise insulation. The leak's origin is then determined by inspecting two primary areas:

1. Audi Valvelift System (AVS) Actuator: If a significant amount of oil is found beneath the AVS actuator, the leak is attributed to its O-ring. Technicians are instructed to document this with photos, replace the O-ring, clean the area, and replace any oil-soaked noise insulation.
2. Injector Area: If the AVS actuator is not the source, the technician proceeds to check the injector area. Oil accumulation around the injector and soaked noise insulation in this region indicate an injector-related leak, which points to the cylinder head cover gasket.

Repair Procedure Summary

The repair procedure varies depending on the diagnosed leak source:

For Audi Valvelift System (AVS) Actuator O-Ring Leaks:

1. Remove the engine compartment cover, heat shield, and upper noise insulation.
2. Remove the Audi valvelift system actuator from the affected cylinder.
3. If substantial oil is present, replace the AVS actuator with a new O-ring seal.
4. Clean the engine compartment and replace any noise insulation that is soaked with oil.

For Cylinder Head Cover Gasket Leaks (due to casting residues):

1. Remove the engine compartment cover, heat shield, and both upper and lower noise insulation.
2. Locate the affected cylinder where oil has gathered around the injector.
3. Remove the cylinder head cover and its seal.
4. Carefully inspect the gasket groove in the cylinder head cover for casting residues.
5. Remove any casting residues using a suitable tool, such as a small flat screwdriver, taking care not to damage the seal groove.
6. Install a new seal, re-assemble the camshaft cover, clean the engine compartment, and replace any oil-soaked noise insulation.

Important Warnings

Technicians are specifically advised:

• Do not replace the Audi valvelift system actuator(s) with an O-ring seal when the leak has been determined to be around the area of the injector(s). This prevents misdiagnosis and unnecessary repairs.
• Make sure not to damage the seal groove! during the removal of casting residues.

Required Parts and Tools

Specific parts may be required for this repair, depending on the diagnosis:

• Fasteners, Bolts, Nuts, and Screws: Refer to ETKA/ELSA for specific requirements.
• 06M906048F: Solenoid valve (if applicable)
• 06M103650D: Gasket Cylinders 1-3 (if applicable)
• 06M103649D: Gasket Cylinders 4-6 (if applicable)
• G 12E050S0: Coolant concentrate 1.5L (if applicable)

Warranty Information

This repair is covered under Audi's warranty program for up to 48 months or 50,000 miles, whichever comes first (Claim Type 110). For Certified Pre-Owned (CPO) vehicles, Claim Type G10 applies, requiring owner verification. If the vehicle is outside of warranty coverage, TSB 2053278/9 serves as informational guidance only. All warranty claims must adhere to the Audi Warranty Policies and Procedures Manual.

Service Numbers:

• 1580: Leak on injector (associated with Damage Code 0050)
• 1551: Leak on Audi valvelift system actuator (associated with Damage Code 0010)

Labor Operations

Labor operations are detailed for both 3.0L and 2.9L (RS models) engines, covering tasks such as removing and reinstalling valvelift system adjusting mechanisms, camshaft adjusters, camshaft housings, and cleaning engine components. Additional operations for radar sensor adjustment, driver assist calibration, and camera adjustments may be necessary if applicable.

Owner Action

If you suspect an Audi Q8 cylinder head oil leak or observe any of the described symptoms, it is recommended to schedule an appointment with an authorized Audi service center. Provide them with details of the symptoms you are experiencing. The technicians will use TSB 2053278/9 to diagnose and perform the appropriate repair.

NHTSA ID: 10239680