OBD-II code · Powertrain (generic)

P051B Crankcase Pressure Sensor A Circuit Range or Performance

Same as P051A with the signal in plausible range yet not matching the engine model.

Is it safe to drive with P051B?

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

Common causes

  • Most likelySensor element drifted

Repair at a glance

Difficulty
Easy
DIY friendly
Often, with basic tools
Typical labour
0.5–1.4 h
Emissions test
Likely to fail
Parts involved
Crankcase Pressure Sensor A

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