P23FCCylinder 11 Injector B Air-Fuel Ratio Imbalance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P23FC is reserved for cylinder 11, so it can only belong to twelve-cylinder engines that add an extra injector in every cylinder. Such a pairing is hard to find in public engine data. Volkswagen's W12 illustrates the point: its early versions used twelve injectors in the intake manifold, one per cylinder, while the 6.3 FSI of the Audi A8 L W12 switched to direct injection with six-hole high-pressure injectors, again one per cylinder. Neither layout has an injector B. Any twelve-cylinder engine built with dual injection would still fall under CARB's imbalance rule, including the expectation that the code names the cylinder to the extent the detection strategy permits. No manufacturer documents P23FC. Should it appear, compare P21A6, P0311 and the circuit code P21D9 before replacing anything.
- What you may notice
- Check engine light on
- Hardly any change in smoothness on a twelve-cylinder engine
- Likely causes
- PossibleSecond injector of cylinder 11 delivering a wrong quantity
- PossibleIntake leak at cylinder 11
- RareCode read from an engine that has no injector B (scan tool or software issue)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €200 – €1,800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.