P2BB0Alternative Fuel Consumption Too Low
- 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
- On engines that burn compressed natural gas, LPG or another fuel besides petrol or diesel, the controller can estimate how much gas it has injected and compare that with how fast the tank actually empties, judged by tank pressure or level. P2BB0 means the tank drains noticeably more slowly than the injection quantity implies. That points less to a leak than to wrong bookkeeping: a drifting tank pressure or temperature sensor, injectors or a regulator that deliver less gas than commanded (often with lean codes), or the engine having run on petrol longer than assumed. No manufacturer documents P2BB0 publicly. FCA patented exactly this consumption balance for CNG vehicles, and CARB counts such engines as alternate-fueled vehicles with their own monitoring plans. The opposite case is P2BB1.
- What you may notice
- MIL on, sometimes together with lean mixture codes
- Gas range or gauge reading implausible
- Engine switches to petrol more often than usual
- Likely causes
- PossibleAlternative fuel tank pressure or temperature sensor reading wrong
- PossibleGas injectors or filter restricted, less gas delivered than commanded
- PossiblePressure regulator supplying too little pressure
- RareFuel mode or control software not matching actual operation
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.