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 car's computer is getting a low signal from a sensor that measures how hot the exhaust gases are before they reach a special filter. It's like a thermometer for the car's exhaust, and it's not working right.
The exhaust gas temperature sensor measures the temperature of the exhaust gases before they enter the diesel particulate filter. A low circuit signal indicates that the sensor is not providing the expected voltage to the engine control module.
The P14A4 code is triggered when the powertrain control module (PCM) detects a low voltage signal from the exhaust gas temperature sensor located at the front of the diesel particulate filter on Bank 1. This sensor is critical for monitoring and controlling the temperature of the exhaust gases to ensure proper operation of the diesel particulate filter.
• Check Engine Light is on
• Poor fuel efficiency
• Possible lack of power
• Faulty exhaust gas temperature sensor
• Wiring issues such as short circuits or open circuits
• Faulty PCM
PCM: Powertrain Control Module, the computer that controls the engine and transmission
Diesel Particulate Filter: A filter designed to remove soot and particulate matter from diesel exhaust gases
• Use an OBD-II scanner to confirm the code
• Inspect the exhaust gas temperature sensor and its wiring for damage
• Test the sensor's resistance and voltage output
• Replace the faulty exhaust gas temperature sensor
• Repair or replace damaged wiring
• Reprogram or replace the PCM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $300
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly inspect and maintain the exhaust system
• Ensure proper sensor installation
• Use high-quality fuel to reduce soot buildup
Sensor Issue
• Avoid driving long distances with this issue
• Consult a professional mechanic for an accurate diagnosis
Sensor-related issues may be covered under the vehicle's emissions warranty.
This code has been more prevalent in diesel engines due to the complexity of their exhaust systems and the need for precise temperature monitoring.
Moderate – It should be addressed soon to prevent potential damage to the diesel particulate filter.
Ignoring this code may lead to increased emissions, which can be illegal in some areas.
• Engine at operating temperature
• Vehicle at idle
The sensor is located in the exhaust system, upstream of the diesel particulate filter on Bank 1.
Q: Can I drive with a P14A4 code?
A: It's not recommended to drive for long periods with this code, as it can affect the vehicle's performance and emissions.
Q: How do I know if the exhaust gas temperature sensor is bad?
A: A faulty sensor may cause poor fuel efficiency, lack of power, and trigger the Check Engine Light.
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