P2A6AAlternative Fuel Rail Pressure Regulator Inlet Pressure Sensor Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2A6A flags a regulator inlet pressure reading that is electrically valid but implausible. Upstream of the regulator the value should fall slowly as gas is burned, jump after refuelling and, with the engine at rest, roughly equal cylinder pressure. A reading that stays frozen, climbs while driving, or sits below the regulated rail pressure although the engine runs normally points to a drifting transducer. For scale: GM regulates the Impala bi-fuel rail to 68–130 psi from a cylinder filled to 3,600 psi, and Blackstone's SAN209 regulator accepts up to 4,500 psig. No manufacturer documents P2A6A or its limits; CARB requires a rationality check for inputs like this one. Compare the sensor with a calibrated gauge before replacing parts.
- What you may notice
- Check engine light on
- Gas gauge does not match the actual fill level
- Unexpected switch to petrol or gas mode refused
- Likely causes
- LikelyInlet pressure transducer drifted or contaminated by oil carried in the gas
- PossibleManual or solenoid tank valve closed, so the reading does not change
- RareContact resistance in connector shifts the signal
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €700
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.