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P2BF8

Exhaust Flow Control Valve B Control Circuit/Open

The exhaust flow control valve B reports a control circuit/open condition. Exhaust routing for back-pressure or noise control cannot be commanded reliably.

  • Check engine light: Yes
  • Emissions related: Yes
  • Repair difficulty: medium

Common causes

Ordered by how often each turns out to be the cause.

  • Open in actuator control wireCommon
  • Open actuator coilPossible
  • Pin pushed back out of connector bodyLess likely

Parts involved

  • Exhaust Flow Control Valve B
  • Wiring Harness
  • ECM

P2BF8 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.