Fuel and air

P02D6 — Cylinder 6 Injector Offset Learning at Minimum Limit

Severity: medium Drive with care, to a shop

What P02D6 means

The engine control module continuously trims each injector's opening time so all cylinders run evenly. P02D6 means the learned offset for the cylinder 6 injector has reached the lowest value the ECM allows and cannot go any lower. This usually points to that injector delivering more fuel than commanded, or to another problem making that cylinder run off-target.

Symptoms

  • Check Engine light on
  • Rough idle or engine shake
  • Misfire, especially on cylinder 6
  • Increased fuel consumption
  • Sluggish throttle response
  • Reduced power

Possible causes

  1. Faulty, leaking or clogged cylinder 6 injector
  2. Damaged injector wiring or a poor connector contact
  3. Low or unstable fuel pressure (pump, filter)
  4. Air leak in the intake near cylinder 6
  5. Mechanical cylinder problem such as low compression
  6. Rarely, an ECM software fault

How to diagnose

  1. Scan all codes and freeze frame data, noting any misfire or fuel trim codes
  2. Review short- and long-term fuel trims and injector learning values on a scan tool
  3. Inspect the cylinder 6 injector connector and wiring for corrosion or chafing
  4. Test injector resistance and the ECM control signal with a scope or noid light
  5. Measure fuel pressure and check that it holds after shutdown
  6. Run a cylinder balance test, and swap injectors between cylinders if needed
  7. Smoke test the intake for vacuum leaks
  8. Do a compression test on cylinder 6 if everything else checks out

Common fixes

  • Clean or replace the cylinder 6 injector
  • Repair the wiring or replace the injector connector
  • Replace the fuel filter or pump if pressure is low
  • Repair any intake air leak
  • Reset learned values and update the ECM software if the manufacturer calls for it

Questions and answers

What does P02D6 mean?

The ECM found that the offset learning for the cylinder 6 fuel injector has reached its minimum limit. The usual suspects are the injector itself, its circuit or fuel pressure.

Can I drive with P02D6?

Briefly and carefully, yes, but get it checked soon. Uneven fueling hurts performance and can damage the catalytic converter.

Will clearing the code fix it?

No. If the cause remains, the code will come back. Check the injector, wiring, fuel pressure and intake leaks first.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.