Idle speed RPMs drops with an electrical load - fan at max or head lights on
Idle speed RPMs drops with A/C load - fan at the 1st speed and AC on.

When EACV is disconnected the RPMs drop.
There is no check engine light.
The car engine is strong, starts and drives great.
The alternator has been replaced (the battery light was sporadically flashing and this seems to went away now).

What can be wrong?

Thank you!

Check Alternator FR Signal. Have alternator inspected, if idle speed fluctuates with electrical load. The FR signal communicates to the ECM how "hard" the alternator is working to meet the electrical demands of the car, including the battery and any loads which aren't monitored by the ELD. This square-wave signal varies in pulse width, according to the load on the alternator. The ECM places, approximately, 5 reference volts on the wire. The voltage regulator will drop this signal to approximately 1.2 volts, in proportion to alternator load. The ECM compares the electrical load (ELD) signal with the FR (Charging Rate) signal from the alternator and uses that information to set the idle speed and turn the alternator on and off. This helps fuel economy.