P048A - Exhaust Pressure Control Valve 'A' Stuck Closed

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3    What is this?
Table of contents

P048A Possible Causes

  • Faulty Exhaust Back Pressure Valve
  • Exhaust Back Pressure Valve harness is open or shorted
  • Exhaust Back Pressure Valve circuit poor electrical connection

How do I fix code P048A?

Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

Cost of diagnosing the P048A code

Labor: 1.0

The cost of diagnosing the P048A code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle's make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P048a Description

Exhaust Back Pressure Regulator - Is a variable position valve that controls exhaust back pressure during cold ambient temperatures to increase cab heat and decrease the amount of time needed to defrost the windshield. The Engine Control Module (ECM) uses the measured exhaust back pressure, (ambient) intake air temperature, engine oil temperature and engine load to determine the desired exhaust back pressure. Valve position is controlled by switching the output signal circuit to 12 volts inside the ECM. On/off time is modulated from 0 to 99 % dependent upon the exhaust back pressure desired.
Upon each initial engine start-up, the ECM exercises the exhaust back pressure valve by commanding it to cycle on and off once. If upon start-up the temperature of intake air sensed by the Intake Air Temperature (IAT) sensor is < 37°F (5°C) and the oil temperature sensed by the Engine Oil Temperature (EOT) sensor is between 32°-140°F (0-60°C) it will continue to keep the back pressure valve partially closed. As the oil temperature rises during engine operation, the ECM will control the valve in response to the rising oil temperature.
OBDII Code P048a - Exhaust Pressure Control Valve 'A' Stuck Closed - AutoCodes.com

P048A More Information

Need more information on how to fix the P048A code?
Get Access to Factory Service Manuals

Information for specific makes

  • P048A AUDI Exhaust Pressure Control Valve 'A' Stuck Closed
  • P048A DODGE Exhaust Pressure Control Valve 'A' Stuck Closed
  • P048A FORD Exhaust Pressure Control Valve 'A' Stuck Closed
  • P048A VOLKSWAGEN Exhaust Pressure Control Valve 'A' Stuck Closed

Need more help?

Get the P048a code diagnosed by a professional: Find a repair shop in your area


Help us improve AutoCodes.com. Leave a comment below or tell us if the information above help you fix the code. What are the symptoms on your vehicle for the P048a code? Have you replaced any parts?
Any information is appreciated. Thanks
Top ⇧