P28F8
Exhaust Pressure Too High Bank 2
The exhaust pressure measured on bank 2 exceeds the calibrated maximum. Common causes are clogged DPF, restricted exhaust path, or stuck exhaust brake/back-pressure valve.
The exhaust pressure measured on bank 2 exceeds the calibrated maximum. Common causes are clogged DPF, restricted exhaust path, or stuck exhaust brake/back-pressure valve.
Common causes
- high
DPF clogged with soot or ash
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-2750
- medium
Back-pressure valve stuck closed
A plausible cause — test and verify before replacing parts.
Typical part cost: $220-2750
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 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 P28F8 mean?
P28F8 means "Exhaust Pressure Too High 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 P28F8?
dpf clogged with soot or ash; back-pressure valve stuck closed — 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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