Powertrain, generic (extended)

P222B Barometric Pressure Sensor B Circuit Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P222B means sensor B delivers a clean signal whose value is wrong. GM documents two strategies. On the 3.0 L LGW (2018) and a 2016 engine family the ECM estimates outside pressure from boost pressure, airflow and rpm while driving; sensor B fails if it deviates by more than 20 kPa, or 25 kPa once more than 1.24 miles have passed since the last update. With the engine stopped for over 10 s, B must sit between 50 and 115 kPa, and if MAP, boost and BARO A agree within 10 kPa while B is further away, B is singled out. Both run as Type B over 320 of 400 readings. On GM's 2023-2024 twin-throttle engine, sensor B measures ahead of the bank 2 throttle and is checked against ambient pressure for 2 s.

Likely causes

Sensor B reading with offset or stuck at one value
Leak or restriction in the intake path that distorts the comparison
Boost or manifold pressure sensor fault affecting the estimate

Symptoms

  • Check engine light after two drives
  • Usually no driveability change

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€60–400
Time0.5–2 h

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

Parts involved

barometric pressure sensor

Related codes

P222AP222CP222DP222EP222FP2227

References: gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com.