Ford party air problems

Your problem lies with the air sensor located in the intake manifold, below the intake manifold near the IAC valve. That's your issue; it's not receiving a good signal and is causing this malfunction

Disconnect the air conditioning unit from the wire that goes to the A/C motor at the fuse box and perform the tests you indicated. Drive your vehicle again at the speed where the problem occurs.
If the condition improves, the issue is with the wire that powers the air conditioning motor.
Keep in mind that activating the air conditioning increases fuel consumption and reduces engine power because it's an integrated component, regardless of whether it came from the factory.
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