P0125moderate severityPowertrain
Insufficient Coolant Temperature for Closed Loop Fuel Control
on 2015 Kia Forte 1.8L I4 · FWD
What this code means
The engine is not reaching normal operating temperature quickly enough for the PCM to enter closed-loop fuel control.
Symptoms
- Check Engine Light
- Poor fuel economy
- Extended warmup time
- Rich exhaust smell
Common causes
- Stuck-open thermostat
- Faulty ECT sensor
- Cooling fan running constantly
- Low coolant level
Diagnostic steps
- Monitor ECT warmup time (should reach 160°F within 5-10 min)
- Test thermostat
- Check cooling fan operation
- Test ECT sensor
Repair notes
Replace thermostat. Most common cause.
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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
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1