What it means
The exhaust pressure measured on bank 1 exceeds the calibrated maximum. Common causes are clogged DPF, restricted exhaust path, or stuck exhaust brake/back-pressure valve.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
- The engine or gearbox may go into limp mode
How it works
The exhaust pressure sensor on bank 1 measures back pressure in that side's exhaust path so the engine control module can assess flow and emissions equipment operation. This code sets when bank 1 pressure exceeds the calibrated maximum, often because a DPF or other exhaust path is restricted or a back-pressure valve is stuck closed.
Common causes
Most likely first.
- DPF clogged with soot or ash
- Back-pressure valve stuck closed
Symptoms
- Check-engine light
- Reduced engine power
- Poor acceleration
How to diagnose it
- Record freeze-frame data and check scan-tool exhaust pressure, soot-load, and regeneration data for bank 1 before clearing the code.
- Inspect the bank 1 exhaust path and pressure sensor hoses or ports for damage, blockage, leaks, or disconnected fittings.
- Check whether a back-pressure valve on the bank 1 path is stuck closed or fails to respond to commands, using the manufacturer's procedure.
- Assess the DPF restriction and soot or ash loading on bank 1 using scan data and the manufacturer's diagnostic procedure.
- If the exhaust path is clear, test the bank 1 pressure sensor and its wiring against the manufacturer's specification.
Common fixes
- Clear a blocked bank 1 pressure sensor port or repair a damaged pressure hose.
- Repair or free a stuck back-pressure valve on the bank 1 exhaust path.
- Perform the manufacturer-approved DPF regeneration if soot loading allows it.
- Clean or replace a DPF that is restricted beyond the manufacturer's service limits.
Can I keep driving?
Reduced power and poor acceleration indicate the bank 1 exhaust may be significantly restricted, and continued driving can worsen heat and engine stress. Avoid towing or hard acceleration, and stop if power drops sharply or warning messages require it.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.