P051E Crankcase Pressure Sensor A Circuit Intermittent/Erratic

The crankcase pressure sensor measures pressure in the crankcase ventilation (PCV) against atmosphere; Ford's EcoBoost engines use it for the disconnection check P04DB, which needs a sound sensor. P051E means the signal jumps or briefly drops below or above its limits – physically impossible changes, usually from a loose contact. No manufacturer document available to us uses P051E; Ford, Maserati and FCA use only P051A–P051D. The description follows CARB's input component rules.

Likely causes

Symptoms

• Check engine light on
• Usually no change in driving
• Disconnection check P04DB suspended

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: law.cornell.edu, fordservicecontent.com.