P23FF code meaning
Bank 2 System B Air-Fuel Ratio Imbalance
Powertrain system Generic code P23xx codes Check engine light
What P23FF means
P23FF mirrors P23FE for bank 2 and can only occur on V, W or boxer engines, because inline engines have no second bank. It means the cylinders on the side without cylinder 1 deviate from each other and the fault is assigned to injection system B, which on Ford's PFDI engines is the port path (lean and rich codes P2BF2/P2BF3). Bank-level monitors on such engines are documented, but under the general codes: GM's 2019 LT5 Corvette V8 fails bank 2 when the normalised oxygen sensor ratio exceeds 0.75, rated Type A and lighting the MIL on the first failed trip, and Ford sets P219B. No manufacturer publishes P23FF. When the fault stays confined to bank 2, the culprit usually sits on that side, such as a port fuel rail, a manifold gasket or several injectors of that bank.
P23FF at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor1 to 5 hours
- Clears after repairAfter a drive cycle
Symptoms of P23FF
- Check engine light on
- Fuel trims of the two banks clearly apart
- Possibly P2BF2 or P2BF3 as well
Common causes of P23FF
- Most likelySeveral port injectors on bank 2 with deposits or wear
- PossibleIntake manifold gasket leaking on bank 2
- Less likelySupply problem in the port fuel rail feeding bank 2
- Less likelyFront oxygen sensor or its wiring on bank 2 distorting the signal
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Fuel system b b2
What each part of P23FF means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 3 | Area: ignition system or misfire. |
| FF | The exact fault in that area. |
What to do next
- Note P23FF and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P23FF
What does P23FF mean?
P23FF means "Bank 2 System B Air-Fuel Ratio Imbalance". P23FF mirrors P23FE for bank 2 and can only occur on V, W or boxer engines, because inline engines have no second bank. It is a generic code, so it means the same on every make.
Is it safe to drive with P23FF?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P23FF fail an emissions test?
Yes, it can. P23FF is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P23FF to fix?
Difficulty: medium. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P23FF clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.