Stange Sounds... IAC?

[Jason_25]

Yeah when I first started hearing it, I thought that it was transmission whine because it sounds alot like big 18 wheelers when they accelerate.

 

[RammaR]

Do you have a subscription to Alldata.com? I wonder if it might have any information about something like this. If Ford has an answer for it, it might be there.

 

[Jason_25]

I sure do. I'll look it up right now.

 

[Jason_25]

Ok no good. Nothing about the whining noise. The more I talk about it the more it annoys me.

 

[CBoug76]

Somebody Please try changing the IAC!!!!!!!!

Even know it is called the IAC(Idle Air Control) IT does NOT necessarly mean that it only controls air at an Idle!


I had the noise you are having, and I changed my IAC, Poof! the Nosie went away!

Here's what you do, since there are 3 of you that are having this problem, Im willing to bet that atleast 1 IAC is bad. FIrst thing you do, have Jason go abnd get an IAC, Jason changes his IAC, if the noise does not go away, have RammaR send you enought $ to pay for the IAC, Now its RammaR's turn, if RammaR's noise does not go away, then he sends it to C Jeff. Now if this does solve your problem, You First have to Thank me! Then tell the other guys that they have to go and buy a replacement IAC......

BUT if this Does not solve the problem, the person who's left with the IAC, can sell it on the For Sale Forum! Im almost positive that it will be bought.

 

[Jason_25]

Chris,

my IAC is brand new!!!!

it made absolutely no difference in the sound!

 

[CBoug76]

Well you never said that before!

 

[CBoug76]

ok I take it back, you did say you had a new IAC...........

 

[RammaR]

So what next? I found another post that said its ok to gently pull off the little cap on the IAC to get to the filters. Even if it breaks then CBoug might get his way finally

But Jason if your's is new.. then what else could it be? I was really hoping the Alldata thing might pan out.

 

[RammaR]

hey guys,

any chance it might be the heat shield on the cat? maybe a haromic there or something?

 

[CBoug76]

If it were a Heat Shield, It would sound like metal rattleing.....(they do not sound a-like)

 

[kgd102]

Well I have a whistling/hissing/ whatever you want to call it noise, kinda of sounds like a supercharger but not quite as loud. So far I have had the power steering fluid flushed and replaced with new, had the tranny fluid flushed and replaced with new, changed fluid in transfer case and differentials. All of this did nothing. Finally as a last resort I bought an IAC today and dropped it in and nothing. Well actually it did solve one noise I was having, for about the last 3 weeks about once every 2-3 days or so I would get this loud ass noise from the front somewhere that sounded like a loud, superloud tea kettle boiling over under my hood. Well the replacement of the IAC seems to have cured that but not the other whistling noise I have. With all that I have done already, anyone got any ideas on what to do next?

 

[Jason_25]

Funny thing about the noise I get is that I can change the pitch of the noise with light throttle inputs.

 

[kgd102]

Same with me. The more throttle I give, the louder it gets. Also, I forgot to mention it but the noise with mine happens during idle and driving. It happens ALL the time. Some day maybe I'll figure it out.

 

[RammaR]

kgd102, unfortunately it sounds like you've got the same or at least a similar problem to me and Jason. However I haven't been able to hear the whistle unless moving. Everything seems to be quiet while in park.

Cboug76, I think you're right about the heat shield sounding different - guess I was just grabbing at straws.

kgd102, do you have a kkm? I heard the noise before I got mine.. but it seems louder afterwards. But I can't say for that's absolutely true. Just thinking that if it got worse that in might still have something to do with the intake side of things.

Jason, how did you clamp the hose (and which hose) to try to stop the "crankcase harmonics"?

Thanks

 

[kgd102]

RammaR - Yeah I have a KKM but it was making the whistling noise long before I got it. It hasn't gotten any worse since getting my KKM either. One of the many times I have had it at the dealer, they told me that the noise was the planetaries spinning and there is nothing out there to quiet or eliminate it. I'm beginning to believe them (since I have tried everything I can think of to get rid of it) but I know there was a point in time that it did not make the noise. I think I just have the luck of having incompetent dealers near me. That whistling noise is the least of my worries compared to the clunking noises I have in the front end. My great ford dealer has had my Sport for about 60 hours to diagnose the noises but they have no clue at all! They can hear it, they can feel it but can't determine what it is. That's the worst part about fords...the service. Sorry for rambling, it's just annoying.

If any of you can think of anything to eliminate the whistling and/or clunking noises please let me know and I forever be indebted to you.

 

[Jason_25]

rammar, I haven't tried the hose clamps yet. Maybe they will work? Also, I may try to get another IAC gasket and see if that helps.

I do not hear the noise in park or at idle. I only hear it down the highway between 1800 and 2200 rpms.

 

[1996XLT-68]

I also have had the whistling problem (under load/throttle), and I can vouch for a fact that it is NOT the IAC valve, since I replaced mine with a Motorcraft one a few weeks ago and no luck.

I think it might be one of the following things:

1. Loose plenum/upper intake
2. worn seal on the throttle body butterfly valve
3. cracked plenum

I guess I'll be diggin into this to see what I can find.

scott

 

[fordkrazy]

i think you guys are going to complicated.....i would look at the fan clutch as that is about the RPM that it engages/disengages. or maybe your fan is missing a fin.....my 94 has lots of cracks in it.

 

[1996XLT-68]

My whistle seems to have more to do with throttle position than RPM, which leads me to believe that it's an intake/vacuum problem and not a fan problem. I will check the fan out though. Thanks!