P0471
P0471-EXHAUST PRESSURE SENSOR 1 PERFORMANCE
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
The Exhaust Gas Pressure Sensor is used to measure exhaust gas pressure in the exhaust manifold. The Powertrain Control Module (PCM) provides a 5 Volt supply to the Exhaust Gas Pressure Sensor on the sensor supply circuit. The PCM also provides a ground on the sensor return circuit. The Exhaust Gas Pressure Sensor provides a signal to the PCM on the Exhaust Gas Pressure Sensor Signal circuit.
- When Monitored:
Five seconds after key on.
- Set Condition:
The Exhaust Gas Pressure Sensor reading at key on differs by a calibrated amount of pressure from the Barometric Pressure Sensor or the Exhaust Gas Pressure Sensor reading varies from an estimated value during normal engine operation.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. CHECK THE EXHAUST GAS PRESSURE SENSOR TUBE AND PRESSURE SENSING PORTS
1. Make sure the pressure hose is connected to the sensor and exhaust manifold. If it is found to be disconnect, connect the hose and retest.
2. Remove the steel tube between the Exhaust Manifold and the Exhaust Gas Pressure Sensor port.
Is the pressure hose and pressure sensor ports located in the manifold free from debris?
Yes
- Go To 2
No
- Clean the hose and pressure sensing port.
- Go To 2
2. CHECK THE EXHAUST GAS PRESSURE SENSOR
1. Turn ignition switch on.
2. Wait five seconds after ignition switch is turned on.
3. With the scan tool, read DTCs.
Is P0471 stored?
Yes
- Go To 3
No
- Replace the Exhaust Gas Pressure Sensor. .
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
3. CHECK THE EXHAUST GAS PRESSURE SENSOR OPERATION
1. With the scan tool, erase DTCs.
2. Start the engine and let it idle for one minute.
3. With the scan tool, monitor the Exhaust Gas Pressure Sensor reading.
Does the value fluctuate slightly, indicating the sensor is not stuck?
Yes
- Repair complete.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace the Exhaust Gas Pressure Sensor. .
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.