2000 Hyundai Accent

Hi Taller Cascante,

P1123 = Short term fuel trim additive air, system too rich.

NOTE:
For air/fuel ratio to be within limits, all sensors, components and systems associated with air/fuel control system must function within normal parameters. The air/fuel control system includes several sensors and the following components and systems:

"Â Intake air system.
"Â Exhaust system.
"Â EVAP control system, including purge control solenoid valve.
"Â Fuel Injectors.
"Â Fuel pump and fuel pressure regulator.

Failure Conditions (Short-Term Fuel Trim)
ECM will set DTC P1123 and illuminate MIL if short-term fuel trim value goes 10-15 percent rich, or if short-term fuel trim additive value is less than 0.4 mS, during 2 drive cycles. ECM will set DTC P1124 and illuminate MIL if short-term fuel trim value goes 10-15 percent lean for 30 seconds during 2 drive cycles. DTC P1123 or P1124 will be set when the following conditions are met:

"Â ECM is in closed loop operation.
"Â Engine speed is less than 1000 RPM.
" Engine coolant temperature is more than 158 °F (70 °C).
"Â EVAP canister purge system is not operating.
"Â Mass airflow is less than 7.5 grams per second (DTC P1123) or 5.5 grams per second (DTC P1124).