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:
• Intake air system.
• Exhaust system.
• EVAP control system, including purge control solenoid valve.
• Fuel Injectors.
• 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:
• ECM is in closed loop operation.
• Engine speed is less than 1000 RPM.
• Engine coolant temperature is more than 158°F (70°C).
• EVAP canister purge system is not operating.
• Mass airflow is less than 7.5 grams per second (DTC P1123) or 5.5 grams per second (DTC P1124).
Nov 4, 2010 at 8:52 AM