P1166 – Fuel Pump Relay Stuck (Ford)

Description

P1166 Ford indicates the fuel pump relay is stuck open or closed.

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Symptoms

  • No start
  • Stalling
  • Hesitation

Causes

  • Relay failure
  • Short circuit
  • Corrosion

Diagnosis

  • Test relay
  • Inspect wiring
  • Check PCM control

Repair

  • Replace relay
  • Repair wiring

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