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 the system in your car that helps reduce pollution by injecting a special fluid isn't getting enough air pressure to work properly.
The reductant injection system uses air pressure to inject a fluid called DEF (Diesel Exhaust Fluid) into the exhaust to reduce emissions. This code indicates the air pressure is too low for the system to function correctly.
The P20E6 code is triggered when the Engine Control Module (ECM) detects that the air pressure in the reductant injection system is below the specified range. This can affect the DEF injection process, leading to increased emissions.
• Check Engine Light illuminated
• Reduced engine performance
• Increased exhaust emissions
• Faulty air pressure sensor
• Leaking air lines or connections
• Malfunctioning air pump
Reductant: A substance used to reduce emissions, often Diesel Exhaust Fluid (DEF).
DEF: Diesel Exhaust Fluid, a liquid used in diesel engines to reduce harmful emissions.
• Verify the code with an OBD-II scanner.
• Inspect the air pressure sensor and connections.
• Check the air pump functionality.
• Replace the faulty air pressure sensor.
• Repair or replace leaking air lines.
• Replace the malfunctioning air pump.
• OBD-II scanner
• Multimeter
• Pressure gauge
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly inspect air lines for leaks.
• Maintain the air pump.
• Periodically check the air pressure sensor.
Emission Control System Issue
• Avoid driving with a persistent Check Engine Light.
• Have the system inspected by a professional.
• Ensure regular maintenance of the emission system.
Check if your vehicle's emission system is covered under warranty, as it may vary by manufacturer and vehicle age.
This code has become more common with the increased use of DEF systems in diesel engines to meet stricter emission standards.
Moderate – Addressing this issue promptly can prevent further emission system damage and avoid failing emissions tests.
Driving with a malfunctioning emission system may violate environmental regulations and contribute to pollution.
• Engine running at normal operating temperature
• Vehicle in a stationary position
The reductant injection system is typically located near the exhaust system, with the air pump and sensor positioned in the engine bay.
Q: Can I drive with a P20E6 code?
A: It's not recommended to drive for extended periods with this code as it can lead to increased emissions and potential damage.
Q: How can I prevent this code from appearing?
A: Regular maintenance of the emission system and checking for air leaks can help prevent this code.
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