Grand AM L4-144 2.4L DOHC VIN T SFI (1997)
Oxygen Sensor: Testing and Inspection
Scan Tool Parameters
A scan tool has several parameters that indicate the state of the exhaust gases: Oxygen Sensor One (O2S 1) voltage, Short Term (S. T.) fuel trim, and
Long Term (L. T.) fuel trim.
Oxygen Sensor Circuit Problems
A problem in the 02S 1 circuit should set a DTC P0134 (open circuit), DTC P0131 (lean exhaust indication), or DTC P0132 (rich exhaust indication). A
faulty or lazy sensor will set a DTC P0133 (slow response) or a DTC P1133 (insufficient switching). See: Powertrain Management/Computers and
Control Systems/Testing and Inspection
