Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car has a special filter that helps keep the air clean. This code means that the filter is clogged, and the car can't go as fast as it should because it's trying to protect the engine.
The P243B code indicates that the diesel particulate filter (DPF) on Bank 2 is restricted, causing the engine control module (ECM) to limit the power to prevent damage.
The diesel particulate filter (DPF) is designed to capture and store exhaust soot to reduce emissions. Over time, the DPF can become clogged with soot and ash. When the ECM detects that the DPF is overly restricted, it triggers the P243B code and limits engine power to prevent damage and excessive emissions.
• Reduced engine power
• Check Engine Light is on
• Increased exhaust smoke
• Clogged diesel particulate filter (DPF)
• Faulty DPF pressure sensor
• Exhaust leaks or blockages
Diesel Particulate Filter (DPF): A device designed to remove diesel particulate matter or soot from the exhaust gas of a diesel engine.
ECM: Engine Control Module, the computer that controls the engine's operation.
• Check for other related codes
• Inspect the DPF for signs of clogging or damage
• Test the DPF pressure sensor for proper operation
• Clean or replace the DPF
• Replace the DPF pressure sensor if faulty
• Repair any exhaust leaks or blockages
• OBD-II scanner
• Pressure gauge
• Basic hand tools
$500 - $2000
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly inspect and maintain the DPF
• Use quality diesel fuel
• Perform regular vehicle maintenance
Emission Control Issue
• Avoid driving the vehicle until repaired to prevent further damage
• Consult with a professional mechanic for diagnosis and repair
DPF-related repairs may be covered under emissions warranty; check with the manufacturer.
This code has become more common as emission standards have tightened and vehicles are equipped with DPFs.
High – Driving with a restricted DPF can lead to engine damage and increased emissions.
Operating a vehicle with an emissions-related fault may be illegal in some areas and can contribute to environmental pollution.
• Engine at operating temperature
• Vehicle driven under normal conditions
The diesel particulate filter is located in the exhaust system, typically near the engine or under the vehicle.
Q: Can I drive with a P243B code?
A: It's not recommended to drive with this code as it can lead to further engine damage.
Q: How often should the DPF be cleaned?
A: The DPF should be inspected and cleaned as needed, typically every 50,000 to 100,000 miles, depending on driving conditions.
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