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2020 MAZDA MAZDA3
2.5L Skyactiv-G I4 (186 hp)•AWD•AUTOMATIC•gas
2 active safety recalls on this vehicle — view recalls
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Repairs0Labor987Torque6478Fluid16DTC2264Battery2Maintenance0Recalls2
P0521high severityPowertrain

Engine Oil Pressure Sensor/Switch Range/Performance

on 2020 Mazda Mazda3 2.5L Skyactiv-G I4 (186 hp) · AWD

What this code means

Oil pressure sensor reading is out of expected range.

Symptoms

  • Oil pressure gauge erratic
  • Warning light flickering

Common causes

  • Sensor fault
  • Oil pressure fluctuating
  • Worn oil pump
  • Wrong viscosity oil

Diagnostic steps

  1. Test with mechanical gauge
  2. Check oil level and condition
  3. Test sensor
  4. Verify correct oil viscosity

Repair notes

Verify actual pressure. Replace sensor if pressure is good.

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