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 in the car's exhaust system, called a fuel injector, is not opening like it should. It helps clean the car's exhaust, and if it's stuck, the car might not run as cleanly.
The P20D6 code indicates that the Exhaust Aftertreatment Fuel Injector B is not functioning properly because it is stuck in the closed position.
The Exhaust Aftertreatment Fuel Injector B is responsible for injecting a precise amount of fuel into the exhaust stream to aid in the reduction of emissions. When this injector is stuck closed, it fails to deliver the necessary fuel, affecting the efficiency of the aftertreatment system.
• Check Engine Light is on
• Reduced fuel efficiency
• Increased emissions
• Faulty fuel injector
• Clogged injector nozzle
• Electrical issue in the injector circuit
Fuel Injector: A device that sprays fuel into the engine's air intake or combustion chamber.
Aftertreatment: A system used to reduce emissions from the exhaust of an engine.
• Use an OBD-II scanner to confirm the code
• Inspect the injector for physical damage or clogs
• Check the electrical connections and wiring to the injector
• Clean or replace the fuel injector
• Repair or replace damaged wiring
• Clear the code and test drive the vehicle
• OBD-II scanner
• Multimeter
• Fuel injector cleaning kit
$200 - $500
Moderate
• Chevrolet Silverado
• Ford F-250
• Ram 2500
• Regular maintenance of the fuel system
• Use quality fuel
• Periodically clean the fuel injectors
Exhaust System Issue
• Have the vehicle inspected by a professional
• Avoid driving long distances until repaired
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has been reported in vehicles with diesel engines that use a complex aftertreatment system for emissions control.
Moderate – It should be addressed soon to prevent further emissions issues.
Driving with this issue may lead to failing emissions tests and potential fines.
• Engine running
• Vehicle at operating temperature
Located in the exhaust system, typically near the catalytic converter.
Q: Can I drive with a P20D6 code?
A: It is not recommended to drive long distances with this code as it can affect emissions and fuel efficiency.
Q: How do I fix a stuck fuel injector?
A: A stuck fuel injector can sometimes be cleaned, but often it requires replacement.
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A wired color-screen reader with readiness hotkeys, live data, code definitions, and data logging.
Good for emissions-related codes because it exposes readiness monitors and live powertrain data.
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Specialty · Smoke machine
Helpful for finding EVAP and vacuum leaks that are hard to see with visual inspection alone.
Helpful for tracking down EVAP and vacuum leaks that can trigger emissions faults.
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Specialty · O2 sensor socket
Helpful when the code points toward exhaust or oxygen-sensor work and space is tight.
Useful when the diagnosis points toward oxygen-sensor removal or replacement.
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Fitment Required · Vehicle-fitment part
Relevant when catalyst-efficiency or emissions faults persist after proper diagnosis.
Catalyst-efficiency faults sometimes point toward converter problems after proper testing.
Catalytic converters are highly vehicle-specific and should not be purchased by code alone.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.