i have a 96 civic ex (d16y8)

i noticed my cooling fan comes on alot even though my car is not even hot, come on alot even at below normal operation temps (its very cold here right now)

now it seems when my car gets to operating temp i dont know if some valve changes somthing or what, but its like all the sudden my car when warm and ran for a while will start to idle really low 500rpm or so steady and i hear a "blowing in a jug or bottle" sound in the intake and manifold

it seems to me like a valve or somthin changes it when it reaches a certain temp, my car does not over heat. i did add a ebay cold air intake recently.

 

hum is probably sucking noise from intake that gets louder a certain rpm.. normal for aftermarket intakes factory have air mufflers on intake to stop that...
fans should come on at certain temp but you may have bad coolent temp sensor Id have to check it out to know for sure??
Id have to hear humm too some gm vehicles hum real loud that is an echo from an intake manifold or vacume leak??