I have a hum/moan sound coming from inside (i think) my intake tube. I only happens when i punch it from a take off and brake quickly before it has a chance to get into 2nd gear. I have to tap the gas (sometimes a few times) to make the hum stop. Truck in sig, auto trans.

 

bump...

also the truck sometimes is humming already from the start up...again have to tap the gas to make it stop...it is pretty loud

 

Check your exhaust shields
Rich

 

Sounds like the noise our 4.0 explorer used to make, it was really annoying. We never fixed ours before trading it in, but I remember reading something about the idle air control valve sticking and causing the noise, it was apparently pretty common on the 4.0's. May be a place to start for you.

 

I have/had the same exact issue. The hum would only go away once I gave it some gas. I read that it was the idle air control valve so I replaced mine and it went away. Sadly, the noise is now back after only having the new valve on the truck for a month. Could it be something else?

 

I have the same hum on my 02 5.4 It happens randomly, mostly while at idle. Its been doing this for about 3 years. I could never figure out what it was. I could tell you that I opened the clamp that holds the air filter in place and opened it up a little and it stopped. Has something to do with the air flow i would imagine.

 

mine is starting to hum again...a little...it is the idle air control valve they last about a year in my truck....this will be #3....the hum doesn't seem to hurt the engine or effect anything...just annoying

 

What brand part did you use?

 

I used a Napa brand part. Figured it would be cheaper than getting it from Ford.

 

i have used 2 motorcraft and this last one was a cheap one from orielly's and it has lastest the longest

 

I had a slight hum and bad gas mileage, noticed a 200 rpm drop when i turn the a/c on, in park idling, and a hiccup at a stop light , changed out the BWD brand IAC I just replaced 3 months ago, from Orielys, with a motorcraft one. Hopefully the motorcraft last longer.