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 computer thinks there is a problem with how fuel is being sent to the system that cleans the exhaust. It's like if a toy car isn't getting enough battery power to run properly.
The code indicates an issue with the system that controls the fuel supply to the exhaust aftertreatment system, which is responsible for reducing emissions.
The P20D8 code is triggered when the Engine Control Module (ECM) detects a performance issue in the fuel supply control for the exhaust aftertreatment system. This system is crucial for reducing harmful emissions by treating exhaust gases before they are released into the atmosphere. The code suggests that the fuel supply to this system is not operating within the expected parameters.
• Check Engine Light is on
• Reduced engine performance
• Increased exhaust emissions
• Faulty fuel supply pump
• Clogged fuel filter
• Malfunctioning fuel pressure sensor
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, second generation
• Use an OBD-II scanner to confirm the code.
• Inspect the fuel supply pump and lines for damage or clogs.
• Test the fuel pressure sensor for proper operation.
• Replace the fuel supply pump if faulty.
• Clean or replace the fuel filter.
• Replace the fuel pressure sensor if malfunctioning.
• OBD-II scanner
• Fuel pressure gauge
• Wrench set
$200 - $600
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regular maintenance of the fuel system
• Use high-quality fuel
• Replace fuel filters as recommended
Engine Performance
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional mechanic.
• Avoid driving long distances until the issue is resolved.
Check with your vehicle manufacturer for specific warranty coverage related to emissions systems.
This code has become more common with the introduction of more stringent emissions regulations and the increased complexity of aftertreatment systems.
Moderate – While not immediately dangerous, it can lead to increased emissions and reduced performance if not addressed.
Driving with a malfunctioning emissions system may violate emissions laws and contribute to environmental pollution.
• Engine at operating temperature
• Vehicle in closed-loop operation
The exhaust aftertreatment fuel supply components are typically located near the exhaust system, often under the vehicle.
Q: Can I drive with a P20D8 code?
A: It's not recommended to drive for long periods with this code, as it can lead to increased emissions and potential damage to the aftertreatment system.
Q: How can I clear the P20D8 code?
A: After repairs are made, you can clear the code with an OBD-II scanner. If the problem is fixed, the code should not return.
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