Air Intake Whistling noise

[ahent]

Ok, so I had an issue with my throttle body on my '07 Explorer. It was not idling correctly when the air conditioning was on. So I get it back and the whistling is still there, but it's a higher pitch (not much just slightly) but still there. So I would assume it is something to do with the throttle body itself otherwise the change of throttle body wouldn't have changed the sound (all other parts are the same). So, that brings me back to what I thought a while ago, would putting something such as "the Tornado" change the airflow through the throttle body enough to eliminate the noise? Oh well, just thought I would post more info.

 

[SirManny]

I have a 07 Mercury Mountaineer Premier AWD with 79xxx miles on it completely stock. My truck just started making that whistling sound on Tuesday well at least thats when I noticed it. I noticed that if Im sitting still and Im in my garage or near a wall that amplifies the sound that pitch of the sound changes as I go from P, R, N, D, 2 and 1. So I figured transmission so as with Fords ill fated design you cant check the trans yourself to see if its low on fluid and the dealer wanted $57 just to check it. I took it to Aamco where they checked the fluid level with the special tool for free. The fluid level checked out fine and is clean. The mechanic didnt orginally hear the noise until he turned my truck on and went to back it out of the bay. He started to diagnose the sound but assured me it wasnt coming from the transmission and sent me on my way after an hour and couldnt pinpoint the sound. I then took it to another trans shop where when I explained to the service writer who happened to be a former Ford Master Tech told me that on the 4.0s they have an issue with the throttle body and the pcv valve but its on the back side of the motor being dirty/clogged and damaged. They cleaned my throttle body and replaced the pcv which was only around $64 plus labor and my whistle is gone.

 

[FlyboyZR1]

I've got this same whistling noise on my Ford Ranger 4.0 XLT. It's only when the engine is under a load, and is present when the throttle is about 1/2 open. It's very high pitched, but not very loud. It seems to have appeared after I cleaned the throttle body?

Has anyone else ever cleaned their throttle bodies with throttle body/carb cleaner. I guess that can remove the teflon coating which can cause a whistling noise present during acceleration:

http://www.ozmazdaclub.com/forums/6...-read-before-cleaning-your-throttle-body.html

 

[Silversn95]

I had some time a couple weekends ago so I took the clean air duct off and removed the throttle body. Behind the throttle body is a diffuser (for lack of a better term) plate with vertical fins. I removed this and cleaned everything. The plate is there to actually attempt to prevent induction noises as air flows past the blade. If I remember correctly, the bore of the throttle body has a larger diameter than the bore on the intake. The plate steps down the diameter between the two. If there is significant missmatch between these parts you can get a whistle. I tried to bias the throttlebody high on the flange when I bolted everything back up to see if it would make a difference. There isn't much you can do without modifying the plate as it has alignment pins that locate it to the manifold. Since doing this I have heard a change in pitch from this whistle but it is still there. A couple other observations: there are multiple secondary air entry points just behind the throttle body flange, these always present the potential to create whistle noises. The EGR tube also protrudes into the air flow, an edge on this tube could also be cause for noise. I also found a step between the welded shells of the intake on the floor of the ziptube (length of manifold air duct before reaching the plenum). A raised edge like this might also be a noise source. I plan to work on this when the weather warms back up but I am convinced this is induction air flow noise and nothing more serious.

 

[Sams01XplrSprt]

2006 u got sound clip of ur dual exhaust

 

[smmn25]

same hissing/whistling sound....

2007 Mountaineer Premier 4.0. The hissing/whistling sound is most prevalent around 2000-2500 rpms during gradual acceleration....more aggressive acceleration and the sound disappears. Ford Master Tech thinks its an air intake sound due to plastic parts and hinted that it might be a "normal" characteristic of the engine. He said if there were a leak, the check engine light would come on. Engine performance is fine, the sound is completley annoying. It seems like there would be an easy fix. Anyone find one yet?

 

[NHarris]

My 05 does it. I think it sounds cool, but I have an aftermarket intake. I would first try tightening the clamps

 

[Brillig]

I noticed there is a rather large gap between the air intake manifold and the throttle body mounting plate (see the photo). I was wondering if this is why it makes that whistling noise. Anyone else with this problem have a similar gap? By the way this is the 4.0L on a 2008 XLT 4x4.

 

[NHarris]

I noticed there is a rather large gap between the air intake manifold and the throttle body mounting plate (see the photo). I was wondering if this is why it makes that whistling noise. Anyone else with this problem have a similar gap? By the way this is the 4.0L on a 2008 XLT 4x4.

Its sealed off. There is a built in O-ring if you take that piece off.

 

[Brillig]

I'm sure there is a seal of some kind in there, but usually these things are designed so that the two pieces bottom out before the o-ring is 100% compressed to prevent it from being distorted or torn. If that's the case, then the gap would indicate that something didn't go together quite right. Compare to the much smaller gap between the aluminum piece and the interface plate in the middle.

Or perhaps it's just poorly designed.

In any case, one of these days I'll have to take it apart and see if I can't get that noise to go away. It drives me crazy.

 

[StrikersCA]

This should help you out:

http://www.explorerforum.com/forums/showthread.php?t=307160

 

[NHarris]

I'm sure there is a seal of some kind in there, but usually these things are designed so that the two pieces bottom out before the o-ring is 100% compressed to prevent it from being distorted or torn. If that's the case, then the gap would indicate that something didn't go together quite right. Compare to the much smaller gap between the aluminum piece and the interface plate in the middle.

Or perhaps it's just poorly designed.

In any case, one of these days I'll have to take it apart and see if I can't get that noise to go away. It drives me crazy.

I tried to get rid of that noise for ages. It bugged me forever and I just decided to live with it. Now that I don't have my 05 I have no issue with the whistle.

If you find the solution to it definately let us know what it is.

 

[Brillig]

Well, I broke down and paid someone else to clean my throttle body instead of doing it myself. Anyway, the noise is less noticeable now. It's not gone, it's just harder to hear. Also, the throttle response is much smoother at low speeds now. No more jolting when I get back on the gas after slowing down in traffic.

 

[xwasif]

AC Issue

hi There

I just bought a 2006 XLT Explorer & I'm facing an issue with the AC considering that it's an explorer , first of all I live & work in Saudi Arabia , the temp out side right now is 50C , I always feel like the AC is not giving that much , I know it's too hot in here but still , comparing Explorer Ac with GMC Yukon , it's very bad , one more thing , when I shut down the AC I hear a sound like if there is something releasing GAS I don't know what this is & I would appreciate all the help I can get

Thanks

Really love the site

 

[bigdogwalker]

Blower motor whistle

I have a 2005 Explorer XLT V-8 / 4.6. When I turn on the air conditioning the blower motor makes an unbearable whistling noise. Does anybody know whats up with that?

 

[SCHOE2]

End of the whistling

As most of you know if you own an Explorer you will get an intolerable whistling coming from the intake somewhere. I tried everything and got no satisfaction. I was on the verge of replacing the IAC (the one on the side of the intake manifold on the 4.0L OHV engine) when I came upon one of the members discussing his whistling and what he did about it before buying another IAC valve for a 100 bucks. He pulled the little black plastic cap off of the valve and opened it up to find 2 small filter disks that had become very dirty and plugged. He removed the disks and replaced the cap and... no more noise. I did the same to my buggy last night and my noise went away as well. The noise is not there at engine start but when you run it on a hot day, shut it off for a while and then restart the engine, you get the dreaded "howling" noise. I will say that I went over my intake system looking for any leaks and checked everything. The noise would go away if I pulled the electrical cord off of the valve which told me where the problem was located. Pull the disks out of the plastic cap and say goodby to the noise. I plan on getting some other filter material for the cap but for now I have no noise.

 

[Brillig]

The IAC valve noise was pretty common in older explorers and rangers, but 2004 and later 4.0 explorers don't have an IAC valve. They have an electronic throttle, which adjusts idle air by varying the throttle plate position. So, if you have a 2004 or later explorer with a whistling noise, try cleaning your throttle body. It made a huge improvement in mine.

Sorry guys, I don't know anything about AC system noise issues. You should probably start a new thread for that.

 

[Commtech]

I recently bought my daughter a 2002 Sport Trac and she is having issues with the car dieing on the road. When we bought it, there was an aftermarket intake on it. I heard the airflow and thought it was a normal issue from the intake ( I changed filters on my old 93 and could hear the airflow afterwards).
She has had it die 2 times now on her and she lives in another town. I had her take it to the shop the first time to pull codes and check it out, ran fine next morning on way to shop. They found nothing and ran cleaner through the jets.
The next time the car died, they said it was the intake and wanted to replace the MAF sensor as well as the IAC. I did convince them to try cleaning the MAF before replacing it, but to go ahead with the IAC replacement...
Getting expensive now, and I am 600 miles away on vacation instead of in next town. told her if this happens again, she is getting my Mountaineer for a month and I will drive the Ex to figure out whats doing this.

 

[Ford Is Better]

The whistling noise will occur when an aftermarket intake is installed on almost any vehicle. It is simply the result of the aftermarket intake being paired with the stock throttle body, and is not harmful in any way. The difference in the inner diameters of the two parts leads to the noise. The solution is to either ignore the noise or to buy an aftermarket throttle body that better matches the intake.

 

[SCHOE2]

Whistling noise solution

Actually the solution for the noise problem is to look at the IAC valve. Take the plastic cap off and remove the fiber disks inside. The noise will go away. It is that simple because I did it on mine and presto, no whistling!