Fuel and air

P02F0 — Cylinder 3 Injector Circuit Range/Performance

Severity: medium Drive with care, to a shop

What P02F0 means

The engine control module drives the cylinder 3 fuel injector and monitors the current and voltage in its circuit. P02F0 sets when the circuit's electrical behavior or response falls outside the expected range, which does not always mean a full open or short. The cause can be the injector itself, the wiring, the connector or, less often, the injector driver inside the module.

Symptoms

  • Check Engine light on
  • Rough idle
  • Cylinder 3 misfire
  • Reduced power and sluggish acceleration
  • Higher fuel consumption
  • Hesitation or jerking under load
  • Hard starting

Possible causes

  1. Faulty cylinder 3 injector (clogged, bad coil or mechanical fault)
  2. Poor connector contact at the injector: corrosion or loose terminals
  3. Open, chafed or shorted wiring to ground or power
  4. Faulty injector driver in the PCM (rare)
  5. Fuel pressure problem
  6. Air leak skewing the air-fuel mixture
  7. Low or unstable system voltage

How to diagnose

  1. Scan all codes and freeze-frame data, and look for misfire codes such as P0303
  2. Inspect the cylinder 3 injector connector and wiring for corrosion, rubbing or oil contamination
  3. Review fuel trims and cylinder balance data on a scan tool
  4. Swap the cylinder 3 injector with a neighboring one and see if the fault follows
  5. Measure injector coil resistance and compare to specification
  6. Check power, ground and the control signal at the connector with a multimeter or scope
  7. Test fuel pressure
  8. Check for intake air leaks and battery voltage

Common fixes

  • Clean or replace the cylinder 3 injector
  • Repair the wiring harness, or replace the damaged connector or terminals
  • Repair or replace the PCM only after ruling out all other causes
  • Fix air leaks or fuel supply problems

Questions and answers

What does P02F0 mean?

The PCM detected that the cylinder 3 injector circuit is operating outside its expected range. The usual culprits are the injector itself or its wiring and connector.

Can I drive with P02F0?

Short trips to a shop are usually fine, but don't drive long distances. Misfires can overheat the catalytic converter and damage the engine.

How do I tell a bad injector from a wiring problem?

Swap the injectors between two cylinders. If the code moves to the other cylinder, the injector is bad. If it stays on cylinder 3, check the harness, connector and PCM.

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.