I own a 2005 Accord EX 4cyl/auto/w/41K mi.It has developed a pronounced "humming" type noise that I traced to the throttle body using a stethescope;it is always present.I have previously posted hearing a high pitched "whining/humming" noise,similar to some type of wind noise or faulty bearing when the car shifts from 2nd to 3rd gear @2000-2500rpm.Someone had suggested the alternator but that was ruled out by my latest technician as well as a tranny issue.Any ideas?Thanks!

 

Just a guess here, is your air filter clean?