P2A76Alternative Fuel Hydraulic Pump 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
- P2A76 is set when the hydraulic pump pressure reading looks electrically sound yet makes no sense for the operating state. Westport's patent explains why a fixed expectation is not enough: pressure rises with hydraulic pump speed, which follows engine speed when the pump is engine-driven, and with the LNG pressure the cryogenic pump works against. The controller therefore corrects its thresholds with a look-up table. A reading that stays flat while the pump strokes, shows no drop at stroke end, or disagrees with downstream fuel pressure points to a drifting sensor, but also to worn pump seals or low oil level. No manufacturer publishes P2A76 or its limits. Compare with a mechanical gauge on the test port and check the oil level.
- What you may notice
- Check engine light on
- Uneven LNG pressure or slow pressure build-up
- Empty-tank warning although LNG remains
- Likely causes
- LikelyHydraulic pressure sensor drifted
- PossibleLow hydraulic oil level or external leak
- PossibleWorn hydraulic pump or drive seals
- 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 – €2,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.