All codes/P049A

P049A

EGR B Flow

Moderate severity

The exhaust-gas recirculation system has a second EGR loop (B) - typically used on engines with a dedicated low-pressure EGR for emissions or on twin-bank V engines. The ECU detects an EGR B flow fault - the measured or modelled flow does not match the requested rate, without yet diagnosing it as too low or too high.

The exhaust-gas recirculation system has a second EGR loop (B) - typically used on engines with a dedicated low-pressure EGR for emissions or on twin-bank V engines. The ECU detects an EGR B flow fault - the measured or modelled flow does not match the requested rate, without yet diagnosing it as too low or too high.

Common causes

  • EGR valve B sticking due to soot

    One of the most commonly reported causes for this code — check this first.

    high

    Typical part cost: $330-1650

  • EGR cooler B partially clogged

    A plausible cause — test and verify before replacing parts.

    medium

    Typical part cost: $330-1650

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First things to check

  1. 1Confirm the code with a scan tool and check for additional related codes.
  2. 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does P049A mean?

P049A means "EGR B Flow". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P049A?

egr valve b sticking due to soot; egr cooler b partially clogged; flow or position sensor drift — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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