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2021 MAZDA MX-5 MIATA

2.0L I4RWDMANUALgas
Repairs0Labor512Torque2472Fluid7DTC919Battery0Maintenance0Recalls0
P0325moderate severityPowertrain

Knock Sensor 1 Circuit Bank 1

on 2021 Mazda MX-5 Miata 2.0L I4 · RWD

What this code means

Malfunction in the knock sensor 1 circuit for Bank 1. The knock sensor detects engine detonation/pinging and allows the PCM to retard timing.

Symptoms

  • Check Engine Light
  • Reduced power (timing retarded)
  • Possible pinging/knocking
  • Poor fuel economy

Common causes

  • Faulty knock sensor
  • Wiring damage
  • Incorrect torque on sensor
  • PCM failure
  • Engine noise masking knock signal

Diagnostic steps

  1. Test knock sensor resistance
  2. Inspect wiring and connector
  3. Check sensor mounting torque
  4. Monitor knock signal with scan tool

Repair notes

Replace knock sensor. Torque to spec (important). Use correct sensor for application.

Other Powertrain codes on this vehicle

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