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P2DDC

Fuel Injection Quantity C Lower Than Expected

The measured fuel injection quantity for group C is below the calibrated window. Injector flow drift, rail pressure off, or measurement bias.

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

Common causes

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

  • Injectors partially cloggedCommon
  • Fuel rail pressure lowPossible

Parts involved

  • Fuel Injector Group C
  • Fuel Rail
  • ECM

P2DDC 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.