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 there's a problem with a sensor that checks if a part of the engine that cools down exhaust gases is working right. It's like when a thermometer isn't giving the right temperature reading.
The P249B code indicates an issue with the sensor that monitors the position of the EGR cooler bypass valve, which is not sending consistent signals.
The Exhaust Gas Recirculation (EGR) system reduces nitrogen oxide emissions by recirculating a portion of the engine's exhaust back to the engine cylinders. The EGR cooler bypass valve allows exhaust gases to bypass the cooler under certain conditions. The position sensor for this valve on Bank 2 is sending erratic or intermittent signals, indicating a potential issue with the sensor or its circuit.
• Check Engine Light illuminated
• Reduced engine performance
• Increased emissions
• Faulty EGR cooler bypass position sensor
• Wiring issues such as frayed or damaged wires
• Poor connection or corrosion at the sensor connector
EGR: Exhaust Gas Recirculation
Bank 2: The side of the engine opposite Bank 1, typically the side with cylinder 2.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the EGR cooler bypass position sensor for proper operation.
• Replace the EGR cooler bypass position sensor if faulty.
• Repair or replace any damaged wiring or connectors.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regular maintenance of the EGR system
• Ensure proper electrical connections
• Routine checks for wiring integrity
Sensor Issue
• Address the issue promptly to avoid increased emissions.
• Consult a professional mechanic if unsure about the repair.
Check with the vehicle manufacturer for specific warranty coverage related to emissions components.
This code has become more common with the increased use of EGR systems to meet emissions standards.
Moderate – While the vehicle may still be drivable, it can lead to increased emissions and reduced performance.
Driving with a malfunctioning EGR system can lead to emissions violations and potential fines in areas with strict emissions laws.
• Engine at operating temperature
• Vehicle in closed-loop mode
The EGR cooler bypass position sensor is typically located near the EGR cooler on the engine, on Bank 2.
Q: Can I drive with a P249B code?
A: While you can drive with this code, it's not recommended as it can lead to increased emissions and reduced engine performance.
Q: How can I prevent this code from appearing?
A: Regular maintenance of the EGR system and ensuring all electrical connections are clean and secure can help prevent this code.
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Helpful for finding EVAP and vacuum leaks that are hard to see with visual inspection alone.
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Helpful when the code points toward exhaust or oxygen-sensor work and space is tight.
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