P2A87Alternative Fuel Pump C Compression Stroke Valve Control Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2A87 covers the control circuit of the compression stroke valve on alternative fuel pump C, reporting an open or otherwise unusable circuit. A third pump valve only exists on systems with at least three separately switched pumping units. Caterpillar's patent US10060421B2 is such a case: it describes six elements arranged around one pump body, allows an odd number as well, and fires each through its own solenoid in a timed sequence. If valve C drops out, the sequence has a gap, delivery becomes uneven and the controller has to fire the others more often to hold gas pressure. No manufacturer publishes P2A87 or assigns the letter C. Check coil resistance and terminals, and whether codes for valves A or B are present as well.
- What you may notice
- Warning lamp on
- Uneven gas pressure, slight power loss at high load
- Likely causes
- LikelyOpen wire or loose connector at valve C
- PossibleSolenoid coil of valve C open
- RareOutput stage for valve C faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €150 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.