2021 Audi Q7/Q8 Hissing Noise and DTC P227900

Symptoms

Owners of affected 2021 Audi Q7 and Q8 vehicles may experience a noticeable "MIL on" (Malfunction Indicator Lamp) illuminated on the dashboard. A common accompanying symptom is a distinct "hissing noise from the engine compartment during idle." This "Audi Q7/Q8 hissing noise" indicates a potential issue within the engine's intake system.

Fault Codes / DTCs

When diagnosing the issue, technicians will typically find a specific Diagnostic Trouble Code (DTC) stored in the Engine Control Module (ECM), identified as J623 (address word 0001).

Code	Description	Module
P227900	Intake Air System Leak	ECM

This DTC, "P227900 (Intake Air System Leak)", directly points to a vacuum leak within the engine's air intake system.

Diagnosis and Trigger Conditions

The root cause of the "Audi Q7/Q8 hissing noise" and the P227900 DTC is often an improperly assembled oil fill extension tube. During vehicle assembly, this tube may have been cross-threaded. This cross-threading creates a gap, leading to an intake/vacuum leak at the interface where the extension tube connects to the valve cover. Technicians will inspect this specific area, as shown in Figure 1 of the original bulletin, to verify proper sealing.

Repair Procedure Summary

To resolve the "Audi Q7/Q8 hissing noise" and the P227900 DTC, technicians will perform an inspection of the oil fill extension tube and its connection to the valve cover. The primary goal is to verify proper sealing of these components. If any damage from cross-threading is identified during this inspection, the affected components will need to be replaced. The repair procedure involves removing and reinstalling the oil fill tube, as detailed in Technical Service Bulletin 01 21 95 2054795/2.

Required Parts and Tools

For this repair, specific parts and tools are required to ensure a proper fix. Technicians should consult their Parts Department and ETKA for the latest information and part bulletins.

• Gasket: Part Number 06A103483D (Quantity: 1)
• Tube: Part Number 4M0115301K (Quantity: 1)
• Fasteners, Bolts, Nuts, and Screws: As needed per the Repair Manual; refer to ETKA.

Warranty Information

This service is covered under specific warranty conditions. For vehicles up to 48 months or 50,000 miles, Claim Type 110 applies. For Certified Pre-Owned (CPO) vehicles, Claim Type G10 is used, requiring verification of owner eligibility. The Service Number for this operation is 1715, with a Damage Code of 0050. Labor operations include "Oil fill tube removed + reinstalled" (Labor Operation Code 1715 1923) and diagnostic time (GFF 0150 0000). Road tests before and after the service procedure are also accounted for. All warranty claims must adhere to the Audi Warranty Policies and Procedures Manual.

Important Warnings

Owners should be aware that if their vehicle falls outside of the specified warranty period, this Technical Service Bulletin is provided for informational purposes only. The repair may not be covered by Audi warranty in such cases.

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Source: NHTSA ID: 10185628, Audi Technical Service Bulletin 01 21 95 2054795/2