P0131 Lean Test
WARNING: This page is about a different car, the 2010 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.
- The ECM detects that the HO2S 1 Voltage parameter is less than 50 mV.
- DTC P0131 sets within 20 seconds during the lean test when the above condition is met.