All codes/P28FA

P28FA

Exhaust Pressure Too Low Bank 2

High severity

The exhaust pressure measured on bank 2 falls below the calibrated minimum. Common causes are leaks upstream of the sensor, missing DPF substrate, or sensor calibration drift.

The exhaust pressure measured on bank 2 falls below the calibrated minimum. Common causes are leaks upstream of the sensor, missing DPF substrate, or sensor calibration drift.

Common causes

  • Exhaust leak upstream of sensor

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

    high

    Typical part cost: $220-2750

  • Sensor zero point drifted

    A plausible cause — test and verify before replacing parts.

    medium

    Typical part cost: $220-2750

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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 P28FA mean?

P28FA means "Exhaust Pressure Too Low Bank 2". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P28FA?

exhaust leak upstream of sensor; sensor zero point drifted — 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?

This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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