I get a fanlike noise at times inside the car. After 2 mechanics failed to hear anything (Gawd they can be deaf when it suits them) one suggested it may be because of A/C fluid being low. The noise stopped when he switched off the "Econ" switch. This made sense and the noise did sound like liquid coursing through a pipe. After he topped up the fluid and checked everything --- it still makes that same, small but irritating noise.
Any suggestions from you experts?

 

hay listen good to the sound and think!!!!!!!!
I once had a leaf sucked into the air system and the stem was rubbing on the fan cage makeing a noiselike bycycle wheel with baseball card rubbing the spokes