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 system in your car that helps reduce pollution is using too much of a special fluid. It's like when you pour too much syrup on your pancakes and it starts spilling over.
The code indicates that the reductant (usually Diesel Exhaust Fluid, DEF) injection system is injecting more fluid than needed to control emissions.
The P249E code is triggered when the Engine Control Module (ECM) detects that the reductant injection system is injecting more fluid than required. This could be due to a malfunction in the reductant injector, a faulty sensor, or an issue with the ECM itself.
• Check Engine Light is on
• Increased DEF consumption
• Possible reduction in engine performance
• Faulty reductant injector
• Defective NOx sensor
• Malfunctioning ECM
Reductant: A substance, often Diesel Exhaust Fluid (DEF), used to reduce emissions.
ECM: Engine Control Module, the computer that controls engine functions.
• Verify the presence of the code with an OBD-II scanner.
• Inspect the reductant injector for proper operation.
• Check the NOx sensor for faults.
• Replace the reductant injector if faulty.
• Replace or repair the NOx sensor if defective.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $800
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regular maintenance of the DEF system
• Use high-quality DEF fluid
• Regularly inspect emission control components
Emission Control System Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional technician.
• Ensure regular maintenance of the emission system.
Emission-related components may be covered under the vehicle's emissions warranty.
This code has become more common with the increased use of DEF systems in diesel vehicles to meet stricter emission standards.
Moderate – It should be addressed soon to avoid potential damage to the emission system.
Ignoring emission-related issues can lead to increased pollution and may not comply with local emission laws.
• Vehicle must be running.
• DEF system must be active.
The reductant injector is typically located near the exhaust system, close to the catalytic converter.
Q: Can I drive with a P249E code?
A: You can drive, but it's not recommended to ignore the issue as it may lead to further damage.
Q: Will this code affect my vehicle's performance?
A: It may lead to increased DEF consumption and potentially reduced engine performance.
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