What it means
The learned fuel-injector offset for cylinder 2 has reached its maximum limit. The code does not by itself establish whether the injector is under-delivering or identify the cause.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The engine control module learns an offset for cylinder 2 injector A to compensate for differences in its fuel delivery or response. P02CF sets when that learned offset reaches its maximum limit; it marks the upper adaptation boundary for cylinder 2 without proving under-delivery or a particular cause.
Common causes
Most likely first.
- Injector offset adaptation at its maximum limit
- Injector flow or response outside the learned range
- Injector wiring or driver fault
- Fuel pressure or delivery problem
Symptoms
- Check engine light on
- Misfire or rough idle on the affected cylinder
- Increased fuel consumption
- Possible fuel smell or smoke from exhaust
How to diagnose it
- Record freeze-frame data and review cylinder 2 misfire, fuel correction, and injector adaptation values to see when the maximum limit was reached.
- Check whether cylinder 2 injector A was recently replaced and verify that any required calibration information was entered.
- Inspect cylinder 2 injector A's connector and wiring for loose pins, corrosion, or damage that could affect its control.
- Compare cylinder 2 injector response and contribution with the other cylinders using the scan tool.
- Test cylinder 2 injector A flow and electrical control, then verify fuel pressure and supply using the manufacturer's procedures.
Common fixes
- Enter the required calibration information for cylinder 2 injector A if it was missed after replacement.
- Repair damaged cylinder 2 injector A wiring or connector terminals.
- Clean or replace cylinder 2 injector A if testing confirms restricted flow or a response fault.
- Correct a fuel-pressure or injector-driver problem if testing identifies one.
Can I keep driving?
If the engine runs smoothly and the warning light is steady, limit driving and avoid heavy loads until diagnosed. Poor cylinder 2 fuelling can cause misfire, reduced power, and excess emissions; stop if the light flashes or the engine runs very roughly.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.