OBD-II code · Powertrain (generic)

P0321 Ignition/Distributor Engine Speed Input Circuit Range/Performance

Engine speed input from the ignition/distributor is in electrical range but plausibility check fails — slow response, drift, or noise.

Is it safe to drive with P0321?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelySensor drift or pickup gap wrong
  • Less likelySensor element aged beyond calibration window
  • Less likelySensor mounting loose - signal damping

Repair at a glance

Difficulty
Medium
DIY friendly
Often, with basic tools
Typical labour
0.5–2.5 h
Emissions test
Likely to fail
Parts involved
Ignition Distributor

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