2004 ford explorer Oxygen sensor can cause hesitation sometimes. But we need to address the following which can cause hesitation at times it is the hose filter airflow connection below #6. To determine is this is the cause you will have to disconnect the entire hose and run car to determine if it is running better if so, than airflow is need from the junkyard. Pick and pull
Another area of concern or needs checking is the C179 which is the blower rotor speed controller. See highlighted site to determine if a wire is not connected in that area.
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Note: on this particular unit if it is cracked, damage, or not connected properly loose upon inspection you will experience disruption in the car’s movement such as hesitation, jerking, cutting off without notice etc.