What it means
Injection timing performance for cylinder 8 is more advanced than the expected range.
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 monitors the commanded and observed injection timing for cylinder 8. This code sets when cylinder 8's injection event is detected as earlier than the allowed range, which may reflect an injector response, its electrical control, or fuel delivery problem.
Common causes
Most likely first.
- Injector wear, sticking, or restricted flow
- Fault in cylinder 8 injector wiring or connector
- Injector driver or control circuit fault
- Fuel pressure or delivery problem affecting injector response
Symptoms
- Check engine light on
- Rough idle or vibration
- Reduced power or uneven acceleration
- Increased fuel consumption
How to diagnose it
- Record freeze-frame data and inspect cylinder 8 timing or injector data to determine when its event went over advanced.
- Check the cylinder 8 injector connector and harness for corrosion, loose pins, chafing, heat damage, or leakage.
- Use available scan-tool cylinder contribution or injector tests to compare cylinder 8 with the others.
- Test the cylinder 8 injector wiring and control signals for opens, shorts, and poor connections according to the manufacturer's procedure.
- If electrical checks pass, assess the injector for sticking or restricted flow and verify fuel pressure and delivery against the manufacturer's specification.
Common fixes
- Repair damaged or poorly connected cylinder 8 injector wiring.
- Correct fuel pressure or delivery if it is outside the manufacturer's specification.
- Clean or replace a sticking or restricted cylinder 8 injector.
- Repair the cylinder 8 injector driver or control circuit if confirmed faulty.
Can I keep driving?
If the engine is smooth and the warning light is steady, drive only as needed and avoid heavy loads until checked. Stop if it runs roughly, loses power, or the warning light flashes; incorrect fueling can damage emissions-control components.
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.