07 Ford Taurus engine revs up and down during idle?

This is what's vexing me

1. At idle start up, stop light etc, car sounds like someone is revving engine… Yes my foot is off the gas…

2. When turn on ac rpm go up and down even while driving and idle

Can feel vibrations in the gas and break pedal. Any ideas at lost of what else that could be wrong with my 07 Ford Taurus.

Cars check engine light isn't coming on and car isn't pulling codes for some reason we have tried.

So far we have replaced the fuel filter, spark plugs, cracked hose, air control valve, egr valve, alternator and belt, battery, cleaned the throttle body, ignition coil

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