Pop Sound on Heavy Acceleration with Multiple DTCs Set

A pop sound may be heard under heavy acceleration on some 2021-2022 Encore GX and Trailblazer models equipped with the 1.2L engine (RPO LIH).

In addition, one or more of the following DTCs may be set:

  • ABS U0100 (Lost Communication with Engine Control Module)
  • ABS U0140 (Lost Communication with Body Control Module)
  • ABS U026A (Lost Communication with Frontview Camera Module)
  • ABS C2A07 (Engine Control Module Indicated Torque Interface Failed)
  • BCM U0100 (Lost Communication with Engine Control Module)
  • ABS U0151 (Lost Communication with Restraints Control Module)
  • ABS C0501 (Steering Assist Control Actuator Return Circuit)
  • ABS P0606 (Control Module Processor Performance)
  • ECM U1346 (Engine Control Module LIN Bus 2)
  • ECM U060F (Lost Communication with Mass Air Flow (MAF) Sensor Bank 1)
  • ECM P0102 (Mass Air Flow (MAF) Sensor Circuit Low)
  • ECM P0352 (Ignition Coil 2 Control Circuit)
  • ECM P0300 (Engine Misfire Detected)
  • ECM P0351 (Ignition Coil 1 Control Circuit)
  • ECM P228C (Fuel Pressure Regulator 1 Exceeded Control Limits – Pressure Too Low)
  • ECM P25A2 (Brake System Control Module Requested MIL Illumination)
  • EPS U0415 (Invalid Data Received From Antilock Brake System Control Module)


These conditions may be caused by a loose ground located at G106 on the engine. (Fig. 14, Encore GX shown) Tighten the G106 ground nut to specification. No parts are required for this repair.


Fig. 14


For more information, refer to Bulletin #21-NA-215.


– Thanks to Frank Jakubiec

Diagnostic Charge Battery Station Software Update
GM Service Know-How Emerging Issues

Leave a Reply

Your email address will not be published. Required fields are marked *