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 car's system that helps reduce pollution isn't working right because the pressure is too low. It's like when a spray bottle doesn't spray well because there's not enough pressure.
The P20E8 code indicates that the pressure in the reductant (DEF) delivery system is below the required threshold, affecting the vehicle's ability to reduce emissions effectively.
The P20E8 code is triggered when the Engine Control Module (ECM) detects that the pressure in the Diesel Exhaust Fluid (DEF) system is lower than expected. This can prevent the DEF from being properly injected into the exhaust stream, which is necessary for reducing nitrogen oxide emissions in diesel engines.
• Check engine light is on
• Reduced engine performance
• Increased emissions
• Faulty reductant pump
• Leaking reductant lines or connections
• Clogged reductant injector
Reductant: A fluid used in diesel engines to reduce emissions.
DEF: Diesel Exhaust Fluid, a reductant used in selective catalytic reduction systems.
• Check for any visible leaks in the reductant system.
• Test the reductant pump for proper operation.
• Inspect the reductant injector for clogs or damage.
• Replace the faulty reductant pump.
• Repair or replace leaking reductant lines.
• Clean or replace the reductant injector.
• OBD-II scanner
• Pressure gauge
• Wrench set
$200 - $600
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly check and maintain reductant levels.
• Inspect reductant lines for leaks.
• Use high-quality DEF fluid.
Emission Control System Issue
• Do not ignore the check engine light.
• Have your vehicle inspected by a professional if you notice performance issues.
• Maintain regular service intervals to prevent such issues.
Check with the vehicle manufacturer for warranty coverage on emission control components.
The P20E8 code has become more common with the increased use of DEF systems in diesel engines to meet stricter emission standards.
Moderate – While the vehicle may still be drivable, emissions will be higher, and performance may be affected.
Operating a vehicle with this code may result in increased emissions, which could violate environmental regulations.
• Vehicle must be running.
• DEF system must be active.
The reductant system components are typically located near the exhaust system, with the pump and tank often under the vehicle near the rear axle.
Q: What happens if I ignore the P20E8 code?
A: Ignoring this code can lead to higher emissions and potential damage to the emission control system, affecting vehicle performance.
Q: Can I fix the P20E8 code myself?
A: If you have the necessary tools and experience, you might be able to fix it. However, it's often best to consult a professional mechanic.
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