P2196 – O2 Sensor Signal Stuck Rich Bank 1 Sensor 1

Meaning:

When the O2 sensor 1 on cylinder 1 (bank 1) is reading an air/fuel ratio that has strayed so far from the norm, the P2196 happens
The P2196 is triggered when the O2 sensor 1 on cylinder 1 (bank 1) is reading an air/fuel ratio that has strayed so far from the norm

This code is similar to P2195; i.e. O2 sensor 1 on cylinder 1 (bank 1) is reading an air/fuel ratio that has strayed so far from the normal 14.7:1 that the PCM is no longer able to correct the ratio.

Main Symptoms:

Check Engine Light comes on.

Possible Causes:

  • Defective O2 sensor or A/F (air/fuel) ratio sensor
  • Open or short in O2 sensor circuit
  • Defective fuel pressure system leading to too high or too low fuel pressure
  • Fuel leak
  • Leak in engine vacuum or intake air
  • Leak in PCV system
  • Leak in fuel system (tank or hoses)
  • Defective MAF sensor
  • Defective PCM

Diagnostic Steps:

  • Visually inspect all wiring harnesses to O2 sensor circuits, especially sensor 1
  • Check vacuum, fuel tank and PCV systems for leaks
  • Using a scan tool, monitor short and long term fuel trim values and compare with manufacturer specs
  • Also take readings for MAF and O2 sensor 1 and compare with specs
  • Check the resistance of those sensors to ensure they work properly. Replace as necessary

Read More: OBD2 Codes List: Meaning, Fixes, and Free Download