981 · Engine

P0326

Knock Sensor 1 Circuit Range/Performance (Bank 1)

MED SEVERITY

Knock sensor 1 signal is implausible. The DME may retard timing as a safeguard.

SYMPTOMS

  • Check-engine light
  • Rough idle or hesitation
  • Reduced performance
  • Worse fuel economy

LIKELY CAUSES

  • Faulty or drifting knock sensor
  • Wiring/connector fault
  • Mechanical/intake condition skewing the reading
  • ECM/PCM fault (rare)

DIAGNOSIS STEPS

  • Compare knock sensor live data against other sensors for plausibility
  • Inspect wiring and connector
  • Check for related mechanical causes (leaks, restriction)
  • Verify reference voltage and ground
  • Replace the sensor if out of spec

RELATED PARTS

  • Knock sensor
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