Powertrain, generic (extended)

P2C33 Crankcase Pressure Sensor B Circuit Range/Performance

Check engine lightOn

EmissionsRelevant

Drive cycleRequired

Limp modePossible

P2C33 means crankcase pressure sensor B delivers a signal inside its electrical limits that the engine module finds implausible, such as an offset from ambient pressure with the engine stopped or values a running engine cannot produce. Two bulletin families name it. Alfa Romeo reprograms both engine control modules of the 2.9 L V6 biturbo in the 2021–2022 Giulia and Stelvio (18-043-23, 18-007-25) because software set P2C33 among other codes; the later issue mentions limp-in. Maserati's MY21 bulletin MAS002969/A for its F160 six-cylinder and F154 eight-cylinder asks for a software update first when P2C33 is the only code, then checks the sensor, harness and blow-by valve; cold weather may play a part. For sensor A Ford sets P051B above a 0.15 inHg offset at rest or implausible pressure at low air flow.

Likely causes

Engine control software needing an update (Alfa Romeo and Maserati V6/V8)

Sensor offset or drift, partly due to moisture or ice in the port

Faulty blow-by (PCV) valve producing abnormal crankcase pressure

Harness or pin resistance shifting the signal

Symptoms

MIL on, often together with other PCM codes
Limp-in mode possible on affected Alfa Romeo models
Otherwise usually no driveability change

Repair estimate

DifficultyMediumWorkshop job

Parts and labour€80–600

Time0.5–3 h

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

Parts involved

crankcase pressure sensor bwiring harnessecm

References: static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov, fordservicecontent.com.