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Powertrain

P0491

Code meaning and manufacturer information

OBD-II / DTC

Reference meaning

What does this code mean?

The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.

A code identifies a detected condition, not a part that must automatically be replaced.

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A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.

Before replacing a part

Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.

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Manufacturer communications

11

Original wording in English

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AUDI

Summary of all Vin-4-Pin topics for June Check engine light after charging - P0E5E00 Rattle noise from sound generator Vehicle sound malfunction warning Oil leak from oil filter drain off valve Secondary air codes P244000 or P049100 P04F000: EVAP system high pressure purge line performance

ASTON MARTIN

V12 Secondary air injection codes P0492 P0491

AUDI

This bulletin contains diagnosis and repair information for DTC P049100 and P049200.

VOLKSWAGEN

Technical Bulletin (Update Programming, DTCs P0491 and or P2440 stored in the ECM Fault Memory): Current ECM software are causing erroneous faults. This document contains the codes necessary to update the software to diagnose issues

Check vehicle applicability

69

A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.

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MakeModelModel year
Aston MartinDB11 ↗2019
Aston MartinDB11 ↗2018
Aston MartinDB11 ↗2017
Aston MartinDBS SUPERLEGGERA ↗2019
AudiA3 ↗2026
AudiA4 ↗2011
AudiA4 ↗2010
AudiA4 ↗2009

Can I keep driving?

A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.