Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that a part of your car that helps clean the exhaust isn't working right. It's like when a straw is blocked, and you can't blow air through it properly.
The P20A7 code indicates a problem with the performance of the valve that controls air pressure for injecting reductant (like urea) into the exhaust system.
The reductant injection air pressure control valve is responsible for regulating the air pressure used to inject reductant into the exhaust stream to reduce emissions. If this valve is not performing correctly, it can lead to improper reductant injection, affecting the vehicle's emission control system.
• Check Engine Light is on
• Reduced engine performance
• Increased exhaust emissions
• Faulty reductant injection air pressure control valve
• Clogged or restricted air lines
• Electrical issues such as damaged wiring or connectors
Reductant: A substance used to reduce emissions, often urea in SCR systems.
SCR: Selective Catalytic Reduction, a system used to reduce nitrogen oxide emissions in diesel engines.
• Use an OBD-II scanner to confirm the code
• Inspect the reductant injection air pressure control valve for damage or blockage
• Check the electrical connections and wiring for faults
• Replace the faulty reductant injection air pressure control valve
• Clean or replace clogged air lines
• Repair or replace damaged wiring or connectors
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly inspect and maintain the emission control system
• Use high-quality fuel and reductant
• Perform routine vehicle maintenance
Emission Control System Issue
• Have the vehicle checked by a professional mechanic
• Avoid driving the vehicle excessively until repaired
Check with the vehicle manufacturer for warranty coverage on emission control components.
This code has become more common with the increased use of SCR (Selective Catalytic Reduction) systems in diesel engines.
Moderate – It should be addressed soon to prevent increased emissions and potential engine performance issues.
Driving with unresolved emission control issues may lead to failing emissions tests and could be illegal in certain regions.
• Engine at operating temperature
• Vehicle running at a steady speed
The reductant injection air pressure control valve is typically located near the SCR system in the exhaust line.
Q: Can I drive with a P20A7 code?
A: It's possible to drive, but it's not recommended as it can lead to increased emissions and further engine issues.
Q: Is a P20A7 code serious?
A: While not immediately critical, it should be addressed to maintain vehicle performance and emissions compliance.
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