What it means
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.
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 2 measures back pressure in that side's exhaust path so the engine control module can assess exhaust flow and emissions equipment operation. This code sets when bank 2 pressure falls below the calibrated minimum, which can result from an upstream exhaust leak, missing filter substrate, or a drifting sensor.
Common causes
Most likely first.
- Exhaust leak upstream of sensor
- Sensor zero point drifted
Symptoms
- Check-engine light
- Reduced engine power
- Poor acceleration
How to diagnose it
- Record freeze-frame data and compare bank 2 exhaust pressure with engine speed and load on a scan tool to confirm when the reading is low.
- Inspect the bank 2 exhaust upstream of the pressure sensor for leaks, soot marks, damaged joints, or missing components.
- Check the bank 2 pressure sensor hoses and ports for disconnection, cracks, blockage, or incorrect routing.
- Compare the sensor's at-rest and running readings with the manufacturer's specification and check its wiring, reference, and ground.
- If no leak or hose fault is found, inspect the emissions filter or substrate on bank 2 for damage or removal using the manufacturer's procedure.
Common fixes
- Repair an exhaust leak upstream of the bank 2 pressure sensor.
- Reconnect or replace a damaged pressure hose and clear a blocked sensor port.
- Repair a faulty sensor ground, reference, connector, or signal wire.
- Replace a pressure sensor that has drifted outside the manufacturer's specification.
- Restore or replace a missing or damaged emissions filter substrate as required.
Can I keep driving?
The code can cause reduced power and poor acceleration, and an exhaust leak may expose occupants or nearby people to fumes. Limit driving, ventilate the cabin, and stop if exhaust enters the vehicle or power loss makes it unsafe.
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.