ECM Codes
4-cylinder GM - AC Delco MPFI
12 - Diagnostic Mode Enabled 13 - Oxygen Sensor; Open Circuit 14 - Coolant Temperature Sensor Circuit; High Temperature Indicated 15 - Coolant Temperature Sensor Circuit; Low Temperature Indicated 21 - Throttle Position Sensor (TPS) Circuit; Signal Voltage High 22 - Throttle Position Sensor (TPS) Circuit; Signal Voltage Low 23 - Mass Air Temperature (MAT) Sensor Circuit; Low Temperature Indicated 24 - Vehicle Speed Sensor (VSS) Circuit 25 - Mass Air Temperature (MAT) Sensor Circuit; High Temperature Indicated 26 - Quad-Driver (QDM) Circuit, Secondary Injectors 31 - Baro Sensor Circuit; Signal Voltage Low or High 33 - Manifold Absolute Pressure (MAP) Sensor Circuit; Signal Voltage High 34 - Manifold Absolute Pressure (MAP) Sensor Circuit; Signal Voltage Low 35 - Idle Speed Error 41 - Engine Speed Signal Missing 42 - Electronic Spark Timing (EST) Circuit 43 - Electronic Spark Control (ESC) Circuit 44 - Oxygen Sensor Circuit; Lean Exhaust Indicated 45 - Oxygen Sensor Circuit; Rich Exhaust Indicated 51 - Mem-Cal Error 53 - Battery Voltage Too High