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 too much water in the fuel, and the car's computer is getting a high signal from the sensor that checks for water in the fuel.
The engine control module (ECM) has detected a high voltage signal from the Water in Fuel Sensor B, indicating an issue with the sensor or the circuit.
The P238D code is set when the ECM detects a higher-than-expected voltage from the Water in Fuel Sensor B circuit. This sensor is responsible for detecting the presence of water in the fuel system, which can cause engine performance issues if not addressed.
• Check Engine Light is on
• Poor engine performance
• Engine stalling or hesitation
• Faulty Water in Fuel Sensor B
• Wiring issues such as open or short circuits
• Corroded or damaged connectors
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the Water in Fuel Sensor B for proper operation.
• Replace the Water in Fuel Sensor B if faulty.
• Repair or replace 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
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly check and replace the fuel filter.
• Use quality fuel from reputable sources.
• Keep the fuel tank clean and free of contaminants.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Regular maintenance can prevent such issues.
Check with the vehicle manufacturer for specific warranty coverage related to emissions and sensors.
This code has been associated with vehicles that experience fuel contamination issues, particularly in areas with high humidity.
Moderate – It should be addressed soon to prevent further engine performance issues.
Driving with a malfunctioning sensor can lead to reduced engine performance and increased emissions.
• Engine running
• Vehicle at operating temperature
The Water in Fuel Sensor B is typically located near the fuel filter or fuel tank.
Q: Can I drive with a P238D code?
A: It's not recommended to drive for extended periods with this code, as it can lead to engine performance issues.
Q: How do I clear a P238D code?
A: After repairs, use an OBD-II scanner to clear the code and test drive the vehicle to ensure the issue is resolved.
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