P1127moderate severityPowertrain
Long Term Fuel Trim System Too Rich
on 2020 Kia Forte 2.0L I4 · FWD
What this code means
The PCM has detected that the long-term fuel trim system correction has exceeded the rich limit. Similar to P1123 but applies to the overall system-level fuel trim rather than individual bank correction.
Symptoms
- Check Engine Light
- Poor fuel economy
- Black exhaust smoke
- Rich exhaust odor
- Rough idle
Common causes
- Multiple leaking fuel injectors
- Fuel pressure regulator failure
- EVAP system purging excessively
- Faulty MAP or MAF sensor over-reporting airflow
- Stuck-open fuel injector
Diagnostic steps
- Monitor system-level fuel trim on scan tool
- Compare bank-to-bank fuel trims
- Check fuel pressure at idle and under load
- Test EVAP purge valve for leaking
- Inspect fuel injectors for leaks
Repair notes
Diagnose and repair the source of excess fuel delivery causing the rich system fuel trim.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1