P236F code meaning
Cylinder 12 Combustion Performance
Powertrain system Generic code P23xx codes Check engine light
What P236F means
P236F is the ECM's verdict that combustion in cylinder 12 falls short, judged from the evaluated pressure curve rather than from a single limit. No manufacturer documents it, as no twelve-cylinder engine with cylinder pressure sensing is public. BorgWarner states that its pressure glow plug lets the controller correct, cylinder by cylinder, how much fuel is injected and when, with the measured pressure as feedback. A performance code of this type follows when that trimming has used up its range for one cylinder and the result is still off target. For diesels, CARB links combustion sensors to more demanding misfire monitoring. Worn or coked injectors, poor compression, a restricted intake or contaminated fuel are typical findings. Rough running, extra smoke and P0312 may appear alongside.
P236F at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyHard
- Typical labor1 to 10 hours
- Clears after repairAfter a drive cycle
Symptoms of P236F
- Check engine light on
- Rough running
- More visible exhaust smoke
Common causes of P236F
- Most likelyInjector of cylinder 12 coked or worn
- PossibleWeak compression in cylinder 12
- Less likelyContaminated or poor-quality fuel
- Less likelyRestricted intake path
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Cylinder pressure sensor glow plugSensor wiringEngine control moduleFuel injector
What each part of P236F 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. |
| 6F | The exact fault in that area. |
What to do next
- Note P236F 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 P236F
What does P236F mean?
P236F means "Cylinder 12 Combustion Performance". P236F is the ECM's verdict that combustion in cylinder 12 falls short, judged from the evaluated pressure curve rather than from a single limit. It is a generic code, so it means the same on every make.
Is it safe to drive with P236F?
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 P236F fail an emissions test?
Yes, it can. P236F 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 P236F to fix?
Difficulty: hard. A typical repair takes 1 to 10 hours of work. This is a job for a workshop.
Will P236F 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.