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 the car that helps reduce pollution is not working because a valve is stuck closed.
The reductant injection valve is responsible for injecting a fluid into the exhaust system to help reduce emissions. If this valve is stuck closed, it cannot perform its function.
The P208F code indicates that the Engine Control Module (ECM) has detected that the reductant injection valve on Bank 2 Unit 1 is stuck in the closed position. This prevents the proper delivery of Diesel Exhaust Fluid (DEF) into the exhaust system, which is necessary for reducing nitrogen oxide emissions.
• Check Engine Light is on
• Increased emissions
• Possible reduction in engine performance
• Faulty reductant injection valve
• Wiring issues or poor connections
• Malfunctioning ECM
Reductant: A substance used to reduce emissions in the exhaust system.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the reductant injection valve.
• Test the operation of the reductant injection valve.
• Replace the faulty reductant injection valve.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly maintain the exhaust system.
• Use high-quality Diesel Exhaust Fluid.
• Perform periodic inspections of the reductant system.
Emission Control System
• Address the issue promptly to avoid increased emissions.
• Consult a professional mechanic for accurate diagnosis.
Check if your vehicle's emissions system is covered under warranty.
The P208F code has become more common with the increased use of DEF systems in diesel engines to meet emission standards.
Moderate – Should be addressed soon to prevent further emission issues.
Driving with this code may lead to failing emissions tests and is not environmentally friendly.
• Engine at operating temperature
• Vehicle running in closed-loop mode
The reductant injection valve is typically located near the exhaust system on Bank 2.
Q: Can I drive with a P208F code?
A: It's not recommended as it can lead to increased emissions and potential engine performance issues.
Q: What is DEF?
A: DEF stands for Diesel Exhaust Fluid, a solution used to reduce emissions in diesel engines.
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