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 your car that helps clean up the exhaust is stuck open, letting too much cleaning fluid through.
The reductant injection valve is responsible for injecting a fluid called DEF (Diesel Exhaust Fluid) into the exhaust system to reduce emissions. If this valve is stuck open, it can cause too much DEF to be injected.
The P20F7 code indicates that the reductant injection valve on Bank 2 Unit 1 is stuck open. This valve is part of the Selective Catalytic Reduction (SCR) system, which reduces nitrogen oxide emissions in diesel engines by injecting DEF into the exhaust stream. A stuck open valve can lead to excessive DEF consumption and potentially damage the SCR catalyst.
• Check Engine Light is on
• Increased DEF consumption
• Possible engine performance issues
• Faulty reductant injection valve
• Electrical issues with the valve circuit
• Contaminated DEF fluid
DEF: Diesel Exhaust Fluid, a solution used in diesel engines to reduce emissions.
SCR: Selective Catalytic Reduction, a system that reduces nitrogen oxide emissions in diesel engines.
• Scan the vehicle for codes and freeze frame data.
• Inspect the reductant injection valve and associated wiring for damage.
• Test the valve operation using a diagnostic tool.
• Replace the faulty reductant injection valve.
• Repair or replace damaged wiring or connectors.
• Flush and replace contaminated DEF fluid.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $500
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly check and maintain DEF fluid levels.
• Use high-quality DEF fluid to prevent contamination.
• Inspect the SCR system during routine maintenance.
Emission Control System Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if you notice increased DEF usage.
• Regularly maintain the vehicle's emission system.
Emission-related components may be covered under the vehicle's emissions warranty. Check with your manufacturer.
The P20F7 code has become more common with the implementation of stricter emissions standards in diesel vehicles.
Moderate – While the vehicle may still be drivable, emissions may exceed legal limits.
Driving with a malfunctioning emissions system may not only be illegal but can also harm the environment.
• Engine at operating temperature
• Vehicle in closed-loop operation
The reductant injection valve is typically located near the SCR catalyst in the exhaust system, on the side corresponding to Bank 2.
Q: Can I drive with a P20F7 code?
A: While the vehicle may still operate, it is not recommended to drive for extended periods as it may lead to increased emissions and potential damage to the SCR system.
Q: What happens if I ignore this code?
A: Ignoring the P20F7 code can lead to excessive DEF consumption, potential damage to the SCR system, and failing emissions tests.
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Universal · Digital multimeter
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Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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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.