Clogged or restricted fuel injector nozzle due to deposits; Failed injector solenoid or internal mechanical wear; Wiring harness damage or poor electrical connection at the injector; Contaminated fuel or debris in the fuel rail; Low fuel pressure from a weak pump or restricted filter; Engine control module software calibration issue or faulty driver circuit

DTC codes / P02xx · Fuel and air metering (injector circuits) / P02C8

P02C8Cylinder 12 - Injector Restricted

Q: What does code P02C8 mean?

Cylinder 12 - Injector Restricted. P02C8 indicates that the engine control module has detected a restricted fuel injector on cylinder 12, meaning the injector is not delivering the expected amount of fuel for the commanded pulse width. The computer typically compares crankshaft speed fluctuations or fuel trim corrections and flags this code when the imbalance exceeds a calibrated threshold.

P02C8 indicates that the engine control module has detected a restricted fuel injector on cylinder 12, meaning the injector is not delivering the expected amount of fuel for the commanded pulse width. The computer typically compares crankshaft speed fluctuations or fuel trim corrections and flags this code when the imbalance exceeds a calibrated threshold.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

AreaFuel and air metering (injector circuits)

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Rough idle or noticeable vibration, especially when the engine is cold
Misfire-like shudder or hesitation during acceleration
Reduced engine power or poor fuel economy
A distinct ticking or tapping noise from the affected cylinder bank
Hard starting or extended cranking before the engine fires

Common causes, most likely first

Clogged or restricted fuel injector nozzle due to deposits
Failed injector solenoid or internal mechanical wear
Wiring harness damage or poor electrical connection at the injector
Contaminated fuel or debris in the fuel rail
Low fuel pressure from a weak pump or restricted filter
Engine control module software calibration issue or faulty driver circuit

How to diagnose and fix it

Perform a visual inspection of the injector connector and wiring for damage or corrosion
Use a scan tool to check fuel trim and misfire counters for cylinder 12
Run a fuel injector balance test or cylinder contribution test to confirm restriction
Check fuel pressure and volume to rule out a supply issue
Clean or replace the suspect fuel injector after confirming the restriction
Clear the code and verify the repair with a road test and live data review

Why cylinder 12 injector codes mislead

A restricted injector often sets no drivability symptoms because the engine management compensates with fuel trim, so the warning light may be the only clue.
Cylinder 12 is typically found on V12 engines, but some manufacturers number cylinders differently, so always confirm the firing order before condemning an injector.
A clogged injector can be caused by fuel system contamination that affects other cylinders, so replacing only one injector without cleaning the rail may lead to repeat failures.
Electrical faults in the injector circuit can mimic a restricted injector, so resistance and waveform testing should precede parts replacement.
The code can be triggered by a marginal fuel pump that only shows low pressure under load, so a static pressure test may pass while the fault remains.

Can I keep driving with P02C8?

You can usually drive the vehicle short distances to a repair shop, but avoid heavy acceleration or towing because a lean cylinder can overheat and cause catalytic converter damage. If the check engine light begins flashing, stop driving and seek immediate service.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.