P1247 Turbo Boost Pressure Low

Definition

Common causes

• Faulty turbocharger
• Boost pressure sensor failure
• Leaks in the intake system
• Clogged or damaged intercooler
• Faulty wastegate
• Vacuum leaks
• Exhaust restrictions
• Faulty engine control module (ECM)

Common misdiagnoses

• Faulty turbocharger
• Boost pressure sensor failure
• Vacuum leaks
• Exhaust leaks
• Wastegate issues
• Intercooler leaks
• Engine control module (ECM) problems
• Fuel delivery issues
• Air intake restrictions
• Ignition system problems

Troubleshooting steps

1. 1. Check for Additional Codes

   Before proceeding, check for any other related trouble codes that may provide more context to the problem

2. 2. Inspect the Turbocharger

3. 3. Physical Inspection

   Check for any visible damage or leaks in the turbocharger itself, including the compressor and turbine housing

4. 4. Wastegate Operation

   Ensure that the wastegate is functioning properly. A stuck or malfunctioning wastegate can prevent the turbo from building proper boost

5. 5. Check for Vacuum Leaks

   Inspect all vacuum lines and hoses connected to the turbo system for cracks, breaks, or disconnections. A vacuum leak can lead to low boost pressure

6. 6. Inspect Intercooler and Piping

   Look for any leaks in the intercooler and associated piping. A leak in these areas can cause a loss of boost pressure

7. 7. Check Boost Pressure Sensor

   Test the boost pressure sensor for proper operation. If the sensor is faulty, it may not provide accurate readings to the ECM

8. 8. Examine the Turbocharger Actuator

   If your vehicle has a variable geometry turbo (VGT), check the actuator for proper movement and operation. A malfunctioning actuator can prevent the turbo from adjusting to the correct position

9. 9. Inspect the Exhaust System

   Check for any restrictions in the exhaust system, such as a clogged catalytic converter or muffler, which can affect turbo performance

10. 10. Check Engine Timing

    Ensure that the engine timing is correct. Incorrect timing can affect turbo performance and boost pressure

11. 11. Review Engine Performance

    Look for any other symptoms that may indicate engine performance issues, such as misfires, poor acceleration, or unusual noises

12. 12. Clear Codes and Test Drive

    After performing inspections and repairs, clear the trouble codes and take the vehicle for a test drive to see if the code returns. 1

13. 13. Consult Technical Service Bulletins (TSBs)

    Check for any manufacturer-specific TSBs related to the P1247 code, as there may be known issues or fixes for your specific vehicle model. If the issue persists after following these steps, it may be necessary to consult a professional mechanic or technician for further diagnosis and repair