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P029A

Cylinder 1 - Fuel Trim at Max Limit

Per-cylinder fuel trim on cylinder 1 has reached its maximum correction limit. Cylinder running too lean structurally.

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

Common causes

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

  • Injector clogged on cylinder 1Common

Parts involved

  • Injector Cyl1
  • Intake System

P029A 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.