Diagnostic Aids
WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
Check for any of the following conditions:
- Inspect for a contaminated oxygen sensor. If contamination is found, determine the cause and correct the condition before replacing the HO2S.
- Inspect for a damaged wiring harness-Inspect the wiring harness for damage. If the harness appears to be OK, observe the heated oxygen sensor (HO2S) bank 1 sensor 1 display on the scan tool while moving the connectors and the wiring harnesses related to the sensor. A change in the display will indicate the location of the fault.
- Inspect for fuel contamination-Small amounts of water can be delivered to the fuel injectors and cause a lean exhaust indication. A lean exhaust indication can also be caused by too much alcohol in the fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
- Test for the correct fuel pressure-The fuel system will be lean if the fuel pressure is too low or the fuel filter is restricted. In order to determine the cause of DTC P0171 or DTC P0174 monitoring the fuel pressure while driving the vehicle at various road speeds may be necessary. Refer to Fuel System Diagnosis .
- For an intermittent condition, refer to Intermittent Conditions .