P2038 Fault Code

Reductant Injection Air Pressure Sensor Circuit Range/Performance

• What does that mean?
• Symptoms
• Causes
• Solutions

The P2038 fault code indicates an issue with the Reductant Injection Air Pressure Sensor Circuit. This sensor is crucial for monitoring the air pressure in the reductant injection system, which is involved in reducing emissions in diesel engines. If the sensor detects a pressure range or performance that deviates from the expected parameters, the engine control module (ECM) will trigger this code.

• The reductant injection system is part of the selective catalytic reduction (SCR) process, used to convert harmful nitrogen oxides (NOx) into nitrogen and water.
• A malfunction in this system can lead to increased emissions and potentially affect vehicle performance.

What are the symptoms of the P2038 code?

Common symptoms associated with the P2038 fault code are:

• Check Engine light illumination
• Reduced engine performance, including limited power and acceleration
• Increased exhaust emissions
• Potentially poor fuel economy
• System warnings regarding emissions or SCR performance might be displayed on the dashboard.

What causes the P2038 code?

Several factors can contribute to the P2038 code, including:

• Faulty reductant injection air pressure sensor
• Wiring issues or poor connections in the sensor circuit
• Defective ECM or sensor calibration issues
• Blockages or restrictions in the reductant system
• Vacuum leaks affecting air pressure readings.

How to fix P2038?

To resolve the P2038 fault code, the following steps should be taken:

• Inspect and, if necessary, replace the reductant injection air pressure sensor to ensure it is functioning correctly.
• Check the wiring and connectors for signs of damage, corrosion, or looseness, and repair any identified issues.
• Test the ECM for proper operation and reflash or replace if necessary.
• Verify that there are no blockages in the reductant system that could affect air pressure readings.
• Clear the fault codes and perform a test drive to ensure the issue is resolved.