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2023 MAZDA MAZDA3

2.0L I4AWDAUTOMATICgas
Repairs0Labor595Torque3708Fluid9DTC919Battery0Maintenance0Recalls0
P3655high severityPowertrain

GDI Fuel Metering Unit Control Stuck

on 2023 Mazda Mazda3 2.0L I4 · AWD

What this code means

The high-pressure fuel pump metering unit that controls fuel volume entering the pump is stuck, causing incorrect fuel rail pressure.

Symptoms

  • Check Engine Light
  • Fuel pressure too high or too low
  • Engine stalling
  • Hard starting
  • Rough running
  • Fuel smell from engine

Common causes

  • Metering unit solenoid failure
  • Contaminated fuel blocking metering valve
  • Metering unit wiring short
  • Mechanical debris in metering valve
  • PCM driver circuit failure

Diagnostic steps

  1. Monitor fuel metering command vs actual rail pressure
  2. Test metering unit solenoid resistance
  3. Inspect fuel quality
  4. Command metering unit through range with scan tool
  5. Check PCM driver output

Repair notes

Replace high-pressure fuel pump metering unit. May require full pump replacement depending on design. Check fuel quality.

Other Powertrain codes on this vehicle

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