OBD-II code · Powertrain (generic)

P0327 Knock Sensor 1 Circuit Low Input (Bank 1)

The knock sensor signal voltage is below the expected range. Usually points to a piezoelectric sensor that has lost its output, or a short to ground in the signal line.

Is it safe to drive with P0327?

Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.

Common causes

  • Most likelyKnock sensor failed
  • PossibleSignal wire shorted to ground
  • Less likelyConnector pins corroded - high contact resistance

Symptoms

  • Check engine light on
  • Power loss from defensive spark retard
  • Increased fuel consumption
  • Possible audible pinging under load

Repair at a glance

Difficulty
Hard
DIY friendly
Best left to a mechanic
Typical labour
1.5–6 h
Emissions test
Likely to fail
After the fix
A drive cycle is needed before the light stays off
Parts involved
Knock Sensor, Knock Sensor Wiring

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.