Exhaust Back Pressure Sensors are engineered for diesel-powered commercial and heavy-duty vehicles equipped with emissions control systems such as Diesel Particulate Filters (DPFs) and Exhaust Gas Recirculation (EGR) systems. These sensors monitor the pressure within the exhaust system and communicate that data to the engine control module (ECM). The ECM uses this information to optimize engine performance, manage regeneration cycles, and maintain emission compliance. Accurate exhaust back pressure readings are essential for ensuring proper operation of the aftertreatment system and for preventing costly downtime in fleet operations.
Common causes of Exhaust Back Pressure Sensor failure include:
• Soot or carbon buildup in the sensor or pressure lines
• Moisture contamination or condensation inside the sensor
• High vibration or excessive heat from the exhaust system
• Damage to wiring or connectors from road debris or corrosion
Symptoms of a failing Exhaust Back Pressure Sensor may include:
• Reduced engine power or limp mode activation
• Poor acceleration or sluggish throttle response
• Frequent or failed DPF regeneration cycles
• Excessive exhaust smoke
• Check Engine Light or MIL on
The following OBD II error codes are the most commonly found with this product type. In an effort to reduce vehicle emissions, the Environmental Protection Agency (EPA) mandated that all vehicles manufactured after 1996 be equipped with OBD II (On-Board Diagnostics 2) technology. OBD II is now the standard in diagnosing vehicle emissions and system faults, and is implemented across all automotive manufacturers. The codes listed for this product type are common instances that may relate to your vehicle and should be used as a guide only. Walker Products will not be held responsible for any use of this information. It is highly suggested that you consult with a professionally trained mechanic prior to any automotive repair, and that you follow all vehicle manufacturer and EPA guidelines for removal, replacement, diagnostics, OBD II code clearing, ECU, and PCM relearn procedures.
o P0470 Exhaust Pressure Sensor Circuit
o P0471 Exhaust Pressure Sensor Circuit Range/Performance
o P0472 Exhaust Pressure Sensor Circuit Low Input
o P0473 Exhaust Pressure Sensor Circuit High Input
o P0474 Exhaust Pressure Sensor Circuit Intermittent
o P0401 Exhaust Gas Recirculation Flow Insufficient Detected
o P0402 Exhaust Gas Recirculation Flow Excessive Detected
o P2452 Diesel Particulate Filter Pressure Sensor A Circuit
o P2453 Diesel Particulate Filter Pressure Sensor A Circuit Range/Performance
o P2454 Diesel Particulate Filter Pressure Sensor A Circuit Low
o P2455 Diesel Particulate Filter Pressure Sensor A Circuit High