Humming Sound when at idle?

RandyB1986 · #1 (**permalink**) 10-29-2009, 07:26 PM

I have a 2004 F250 with the 5.4 with 120,000 miles. I noticed the last few months when I am sitting at a stop light or drive thru...the truck makes a humming sound. It is like a noise you get when a power steering use to whine or when the power steering had a vacumn problem.

I do know my air conditioning went out this summer. I got to looking and I think there is a hole in the AC condenser, or whatever it is that looks like and is mounted by the radiator.

Any advice, suggestions or thoughts? I could replace the AC part but I really dont need or use the AC but I am tired of this hmmmmmmmmming.

Thanks,
Randy

PW_SD · #2 (**permalink**) 10-30-2009, 12:58 AM

MY 04 F-250 SD 5.4 with 147K does the same thing occasionally at idle. Sounds like a deep hum or howl. Goes away when I raise the RPM slightly.

I saw a post regarding this earlier. If I find it I will post the link. It's on my list to solve as well.

If you find anything, let me know

PW_SD · #3 (**permalink**) 10-30-2009, 01:25 AM

I came across several post with similar symptoms- no resolution

Do you have a stock air-box or K&N? (I have the K&N)

Here are a few links that I came across that appear similar:

http://www.ford-trucks.com/forums/842904-foghorn.html
http://www.ford-trucks.com/forums/78...ing-noise.html
http://www.ford-trucks.com/forums/19...r-shut-up.html

In the last link, a guy provided a reply with three links that don't open for me. Let me know if you have any sucess.

RandyB1986 · #4 (**permalink**) 10-30-2009, 09:05 AM

My truck is all stock, including air box. Does your truck AC work fine? I'll keep you updated. Thanks!

aldridgec · #5 (**permalink**) 10-30-2009, 09:30 AM

Check your PCV valve at idle on the passenger side valve cover. They will vibrate when they wear and cause a noise.

benbishop · #6 (**permalink**) 10-30-2009, 10:04 AM

Yeah, under the hood mine was sort of a humming or buzzing sound. It was a bad PCV valve. $4 and 1 minute to change.

bdschwartz · #7 (**permalink**) 11-05-2009, 09:16 AM

I have a howl when I decelerate on ocassion. Pushing slightly on the accelerator the howl stop immediately. I'm thinking it is the idle air valve. 147K miles and maybe its getting clogged?