Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a leak in the system that helps clean up the bad stuff from the car's exhaust. It's like having a hole in a straw when you're trying to drink a milkshake.
The code P202D indicates that the vehicle's onboard computer has detected a leak in the reductant delivery system, which is responsible for injecting a fluid (like DEF) to reduce emissions.
The P202D code is set when the Engine Control Module (ECM) detects a leak in the reductant system, which is used in diesel engines to reduce NOx emissions. This system typically uses a urea-based fluid, such as Diesel Exhaust Fluid (DEF), which is injected into the exhaust stream. A leak in this system can cause improper dosing and increased emissions.
• Check Engine Light is on
• Increased exhaust emissions
• Possible reduction in engine performance
• Damaged reductant lines
• Faulty reductant injector
• Leaking reductant tank
Reductant: A fluid used to reduce emissions, often Diesel Exhaust Fluid (DEF).
DEF: Diesel Exhaust Fluid, a urea-based solution used in diesel engines to reduce NOx emissions.
• Visually inspect reductant lines and connections for leaks.
• Check the reductant injector for proper operation.
• Inspect the reductant tank for cracks or damage.
• Replace damaged reductant lines.
• Repair or replace the reductant injector.
• Replace the reductant tank if it is leaking.
• OBD-II scanner
• Wrench set
• Leak detection kit
$150 - $600
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly inspect reductant system components.
• Use high-quality DEF fluid.
• Check for leaks during routine maintenance.
Emission Control System Issue
• Have the vehicle inspected by a professional.
• Avoid ignoring the warning light to prevent further damage.
Check with the vehicle manufacturer for possible emissions-related warranty coverage.
The P202D code has become more common with the increased use of DEF systems in diesel engines to meet emissions standards.
Moderate – It should be addressed soon to prevent increased emissions and potential engine performance issues.
Driving with this code may lead to failing emissions tests and increased pollution.
• Engine running
• Vehicle at operating temperature
The reductant system components are typically located near the exhaust system and DEF tank, often under the vehicle.
Q: Can I drive with a P202D code?
A: It's not recommended to drive for extended periods with this code as it can lead to increased emissions and potential engine issues.
Q: How do I know if my reductant system is leaking?
A: You may notice a strong ammonia smell, visible fluid leaks, or the Check Engine Light may illuminate.
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