16785/P0401/001025

16785/P0401/001025 - Exhaust Gas Recirculation (EGR) System: Insufficient Flow Detected

Possible Symptoms

• Malfunction Indicator Light (MIL) ON
• Reduced Exhaust Gas Recirculation (EGR)
• Reduced Power Output/Engine running rough
• Increased Emissions

Possible Causes

• Exhaust Gas Recirculation (EGR) Flow restricted/clogged
• Exhaust Gas Recirculation (EGR) Valve stuck closed/leaking/faulty
• Wiring and/or Connector(s) from/to Exhaust Gas Recirculation (EGR) Valve faulty
• Exhaust Gas Recirculation (EGR) System faulty

Possible Solutions

• Check/Clean Exhaust Gas Recirculation (EGR) System
• Check/Replace Exhaust Gas Recirculation (EGR) Valve
• Check Wiring and/or Connector(s) from/to Exhaust Gas Recirculation (EGR) Valve

Special Notes

When this fault is stored in a 2009-2012 NAR market 2.0L CR TDI (CBEA, CJAA, CKRA) VW Jetta/Golf (1K/AJ) or the NMS Passat (A3) chassis:

• Please see: TSB 26-13-03 | TPI# 2031583/3 (formerly know as 26-12-08 | TPI# 2031583). When the Exhaust Pressure Flap Control Module (J883) is faulty, the engine controller may have any of the following DTCs:
  • P047F/001151 - Exhaust Pressure Control Valve: Stuck Open
  • P0477 - Exhaust Pressure Control Valve "A" Low
  • P048A/001162 - Exhaust Pressure Control Valve 1: Stuck Closed
  • P048B - Exhaust Pressure Control Valve "A" Position Sensor/Switch Circuit
  • P048C - Exhaust Pressure Control Valve "A" Position Sensor/Switch Circuit Range/Performance
  • 16785/P0401/001025 - Exhaust Gas Recirculation (EGR) System: Insufficient Flow Detected
• Some TDI-CR engines have a filter for the EGR that can become restricted and cause a "Insufficient Flow" code.