P1378 – ECM Internal Fuel Timing Error (Nissan)

Description

The ECM detected an internal fuel timing control error.

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Symptoms

  • Hard start
  • Poor acceleration

Causes

  • ECM internal fault
  • Driver failure
  • Signal error

Diagnosis

  • Scan fuel timing data
  • Inspect wiring
  • Test ECM outputs

Repair

  • Repair wiring
  • Replace ECM