Open Loop Mode

The ECM will be in open loop mode when:

• starting the engine.

• hard acceleration.

If the engine will not go into closed loop mode, the problem may be insufficient engine temperature, no response from the oxygen sensor or air/fuel sensor, or the heater circuit is inoperative. Usually, no response from the oxygen or A/F sensor will set DTC P0125.

If there is a driveability problem only in closed loop, anything that disrupts air/fuel ratio, the oxygen or A/F sensor circuit may be the cause.

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Responses

  • RHEA
    Which sensor is use for open loop in car engine?
    3 years ago

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