Fuel and air

P02DA — Cylinder 8 Injector Offset Learning at Minimum Limit

Severity: medium Drive with care, to a shop

What P02DA means

The engine control module continually learns a small correction for each injector so every cylinder gets the same amount of fuel. P02DA means the correction for the cylinder 8 injector has hit its lower limit and cannot be reduced further. This usually points to an injector delivering more fuel than expected, or another problem making that cylinder run rich.

Symptoms

  • Check Engine light on
  • Rough idle or vibration
  • Misfire or hesitation under acceleration
  • Reduced power
  • Higher fuel consumption
  • Fuel smell from the exhaust

Possible causes

  1. Leaking, sticking or dirty cylinder 8 injector
  2. Poor connection or damaged wiring in the injector circuit
  3. Fuel pressure too high or unstable
  4. Air leak or a faulty sensor skewing the mixture
  5. Learning limit reached because of a mechanical problem in the cylinder
  6. ECM software error (uncommon)

How to diagnose

  1. Scan all codes and freeze-frame data, noting any misfire or other injector codes
  2. View fuel trims and per-cylinder learned values on a scan tool
  3. Inspect the cylinder 8 injector connector and harness for corrosion, damage or a loose fit
  4. Measure injector coil resistance and check power and control signal
  5. Test fuel pressure and how well it holds after shutoff
  6. Swap the injector with a neighboring cylinder to see if the fault follows it
  7. Check for intake leaks, and inspect the spark plug and compression on cylinder 8
  8. Check for ECM software updates for the vehicle

Common fixes

  • Replace the cylinder 8 injector, or have it bench tested and serviced
  • Repair the injector wiring or connector
  • Service the fuel system: filter, pressure regulator, lines
  • Fix air leaks or replace a faulty sensor
  • Update ECM software and reset learned values if the manufacturer calls for it

Questions and answers

What does P02DA mean?

The ECM can't lower the correction for the cylinder 8 injector any further because it reached its minimum limit. Most often the injector is delivering extra fuel or something else is enriching that cylinder.

Can I drive with P02DA?

Briefly and carefully, yes, but get it repaired soon. A rich mixture and misfires can damage the catalytic converter and increase fuel use.

Will clearing the code fix it?

No. If the cause remains, the learned value will hit the limit again and the code will return. Check the injector, wiring and fuel pressure.

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.