OBD-II code · Powertrain (generic, extended)

P2A86 Alternative Fuel Pump B Compression Stroke Valve Control Circuit High

The control circuit of the compression stroke valve in alternative fuel pump B reports a control circuit high condition. Pump compression stroke cannot be commanded as expected.

Is it safe to drive with P2A86?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelyControl wire shorted to B+
  • PossibleOpen valve coil
  • Less likelyConnector pins corroded - high contact resistance

Symptoms

  • Check engine light on
  • Hard start, no start, or stalling under load
  • Power loss especially at high load or rpm
  • Possible long cranking time

Repair at a glance

Difficulty
Hard
DIY friendly
Best left to a mechanic
Typical labour
2–6 h
Emissions test
Likely to fail
Parts involved
Alt Fuel Pump B Compression Stroke Valve, Wiring Harness, Afcm

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.