4.0 humming problem
 

So i put a K&N on the good old 4.0, after a week or so it would start to make an unbelievable loud humming noise. it was on and off coming in weeks at a time, so i decided to put the stock filter back on. i thought i fixed the problem but i did not, it still hums but not as loud or as much. any ideas and solutions would be very well apprciated

replace the idle air control valve. seen it a million times