P2A0BManifold Absolute Pressure Sensor B Circuit Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2A0B means the MAP B signal stays inside its electrical range but does not fit the operating state. GM documents it for the Corvette's LT6 V8, where sensor B reads the bank-2 manifold pressure, with several checks: before the engine turns, the raw reading has to agree with ambient pressure within a few kPa, otherwise one trip and 5 s are enough; with the engine running it is held against a modelled manifold pressure and may not overshoot the model's maximum or undershoot its minimum by more than about 2 kPa; and if the signal moves by less than 10 kPa although conditions should make it vary, the sensor is treated as frozen (two trips). Leaks downstream of the throttle, a blocked sensor port, ice or a drifting sensor are typical reasons.
- What you may notice
- Check engine light on
- Hesitation or uneven idle
- Mixture or load faults on bank 2
- Likely causes
- LikelyAir leak in the bank 2 intake behind the throttle
- PossibleSensor port blocked by deposits or frozen condensate
- PossibleSensor B drifting so that its reading no longer matches ambient or model
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €40 – €350
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.