2000-2004 Audi A6/S6 Alternator Air Duct 4B3903423
OEM Part #: 4B3-903-423 (4B3903423)
Actual photo
The exact part you’ll receive — not a stock photo.
$20.99
Used
Donor2001 Audi A6 · 4.2L
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Genuine OEM Used
SKU: 247271
Donor Vehicle: 2001 Audi A6 · 4.2L
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$20.99
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The Audi Alternator Air Duct (OEM part number 4B3903423) is a genuine used OEM component sourced from a donor vehicle. This duct channels cooling air to the alternator on the 4.2L V8 engine found in select Audi models. If the duct is cracked or missing, the alternator can overheat, reducing charging output or causing premature failure—a common issue on these V8s. This is the air intake duct, not the alternator itself.
Specifications
| Fits Vehicle Model | A6, S6 |
| Fits Vehicle Make | Audi |
| OEM Part No | 4B3-903-423 (4B3903423) |
| Category | Battery / Charging / Starting |
Compatible Vehicles
Fits 7 vehicle configurations across 1 make, 2000-2004.
Check your specific vehicle before ordering.
This list shows year, make, and model. Some years have multiple trims or
engines that use different parts, and individual listings may have
additional fitment notes (e.g. “with sunroof only”). Review
the full variant list below, or
message us with your VIN
and we’ll confirm the match.
View all 7 vehicle configurations
| Year | Make | Model | Trim | Engine | Note |
|---|---|---|---|---|---|
| 2001 | Audi | A6 | Quattro Sedan | 4.2L V8 | |
| 2000 | Audi | A6 | Quattro Sedan | 4.2L V8 | |
| 2002 | Audi | S6 | Wagon | 4.2L V8 | |
| 2002 | Audi | A6 | Quattro Sedan | 4.2L V8 | |
| 2004 | Audi | A6 | Quattro Sedan | 4.2L V8 | |
| 2003 | Audi | A6 | Quattro Sedan | 4.2L V8 | |
| 2003 | Audi | S6 | Wagon | 4.2L V8 |