P0491 on the 2011 Audi Q5
The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.
Nobody has written a description of this code yet.
| 26 12 15 2026528 | 2022-05-31. Service bulletin. MIL on. DTC P0491 and P0492 (Secondary Air System Insufficient Flow, Bank 1/2) are stored at the same time. |
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| A011383 2033001- | 2017-11-17. Service bulletin. MIL on. DTC P0491 and P0492 (Secondary Air System Insufficient Flow, Bank 1/2) are stored at the same time. Mileage is greater than 15,000 miles. Under certain driving conditions, the secondary air ports in the cylinder head can accumulate carbon over time, causing a restriction. |
| A261215 2026528- | 2017-11-08. Service bulletin. Supersedes Technical Service Bulletin Group 26 number 12-10 dated March 30, 2012. MIL on. DTC P0491 and P0492 (Secondary Air System Insufficient Flow, Bank 1/2) are stored at the same time. Mileage greater than 20,000 miles. |
3 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.