lean means to much air or not enough gas
The Powertrain Control Module (PCM)
controls the air/fuel metering system in order to provide the best possible combination of driveability, fuel economy and emission control. Fuel delivery is controlled differently during Open and Closed Loop. During Open Loop the PCM determines fuel delivery based on sensor signals, without oxygen sensor
input. During Closed Loop the PCM adds oxygen sensor inputs to calculate Short and Long Term fuel trim (fuel delivery adjustments). If the oxygen sensors indicate a lean condition, fuel trim values will be above 0 percent
. If the oxygen sensors indicate a rich condition, fuel trim values will be below 0 percent
. Short Term fuel trim values change rapidly in response to the HO2S voltage signals. Long Term fuel trim makes coarse adjustments in order to maintain an Air/Fuel Ratio of 14.7 to 1. If the PCM detects an excessively lean condition, this DTC will set. CONDITIONS FOR RUNNING THE DTC
ONDITIONS FOR SETTING THE DTC
- DTCs P0101, P0102, P0103, P0107, P0108, P0121, P0122, P0123, P0130, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0201, P0202, P0203, P0204, P0205, P0206 P0300, P0401 P0403, P0404, P0405, P0410, P0440, P0442, P0446, P0506, P0507, P1404, or P1441 are not set.
- The Engine Coolant Temperature (ECT) is between 20-110°C (68-230°F) .
- The intake air temperature is between 18-70°C (64-158°F) .
- The Manifold Absolute Pressure (MAP) is between 15-105 kPa (2.1-15.2 psi ).
- The vehicle speed is less than 132 km/h (82 mph ).
- The engine speed is between 600-4000 RPM .
- The barometric pressure is more than 70 kPa(10.1 psi) .
- The Mass Air Flow (MAF) is between 5-150 g/s .
- The fuel level is more than 10 percent
- The average Long Term fuel trim value is above 20 percent .
- All of the above conditions are present for 6 seconds .
ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.
CONDITIONS FOR CLEARING THE MIL/DTC
- The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Use a scan tool in order to clear the MIL and the DTC.
|Steps 1-6 |
|Steps 7-8 |
The numbers below refer to the step numbers on the diagnostic table.
- If conditions were not corrected, refer to Fuel System Diagnostics for a possible fuel problem. See: Component Tests and General Diagnostics\Fuel System Diagnosis
- If conditions were not corrected, a worn cam, worn intake or exhaust values or other engine mechanical failures may be at fault.