Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with a sensor that helps the car's system know how much pressure is in the air that is used to inject a special fluid into the exhaust to make it cleaner.
The P2038 code is triggered when the engine control module (ECM) detects a range or performance issue with the reductant injection air pressure sensor circuit.
The reductant injection air pressure sensor monitors the pressure of the air used in the selective catalytic reduction (SCR) system to inject a reductant (such as urea or DEF) into the exhaust stream. This sensor ensures the correct amount of reductant is injected for optimal emissions reduction. A range/performance issue indicates that the sensor readings are outside the expected range or inconsistent with expected performance.
• Check Engine Light is on
• Possible decrease in fuel efficiency
• Potential increase in emissions
• Faulty reductant injection air pressure sensor
• Wiring issues or poor connections in the sensor circuit
• Faulty ECM
Reductant: A substance, often urea, used in SCR systems to reduce emissions.
SCR: Selective Catalytic Reduction, a system that reduces nitrogen oxide emissions in diesel engines.
• Use an OBD-II scanner to verify the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant injection air pressure sensor for proper operation.
• Replace the reductant injection air pressure sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram
• Regularly inspect and maintain the SCR system.
• Ensure proper fluid levels in the reductant tank.
• Perform routine checks on the vehicle's wiring and connectors.
Sensor Issue
• Address this issue promptly to avoid emissions problems.
• Consult a professional mechanic if unsure about repairs.
Check if the vehicle's emissions warranty covers sensor replacement.
This code has become more common with the increased use of SCR systems in diesel vehicles to meet emissions standards.
Moderate – While the vehicle may still run, emissions could be affected, and it should be addressed soon.
Ignoring emissions-related issues can lead to failing emissions tests and potential fines.
• Engine running
• Vehicle at operating temperature
The reductant injection air pressure sensor is typically located near the SCR system or along the reductant injection line.
Q: Can I drive with a P2038 code?
A: While you may be able to drive, it's not recommended as it can affect emissions and fuel efficiency.
Q: Is a P2038 code serious?
A: It's moderately serious due to its impact on emissions, so it should be addressed soon.
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