Howling Explorer !?!?!?

[felsmann]

Same problem here!!

Only on Summers though.

 

[DocVijay]

OK. I have a strange problem that I have not been able to fix. Now that the weather is getting hot again, my Explorer has developed a strange trait. Once the car is warmed up by driving a while, something under the hood starts howling. It only does this while idling, from 750rpm up to about 1200 rpm. I thought it was the intake resonating, but no luck. Please help me diagnose this problem. It only does it when the weather gets hot. Usually if I put it into neutral and rev the engine above 1500, it stops. If I'm driving, it makes no noise. Today, at a stoplight, I tried the neutral/rev thing and it didn't work. It kept howling, and the engine stayed at about 1900 rpm for a few seconds before dropping back to idle. What's going on?

 

[SCEXPLORER]

Originally posted by DocVijay
OK. I have a strange problem that I have not been able to fix. Now that the weather is getting hot again, my Explorer has developed a strange trait. Once the car is warmed up by driving a while, something under the hood starts howling. It only does this while idling, from 750rpm up to about 1200 rpm. I thought it was the intake resonating, but no luck. Please help me diagnose this problem. It only does it when the weather gets hot. Usually if I put it into neutral and rev the engine above 1500, it stops. If I'm driving, it makes no noise. Today, at a stoplight, I tried the neutral/rev thing and it didn't work. It kept howling, and the engine stayed at about 1900 rpm for a few seconds before dropping back to idle. What's going on?

I have the same problem. It just an annoying sound. I sprayed the IAC valve with Gumout like everyone suggested but the sound is still there. So I was wondering if it could still be the IAC valve and that i would need to replace it. How much is a valve and where can i get it? (Pepboys doesn't carry it)

-Ray

 

[MrBean972]

The IAC sounds like a logical solution.

I know AutoZone sells the IAC sensor and it was around i think 35$.

I live in Texas and we have AUtoZones everywhere i dunno about where your at.

 

[David S.]

My X has a howling as well and it shows when it is hot outside and I am using the ac. As for mine, I think it is the new fan clutch that I put in a month or so ago. I was told by a mechanic that the sound, at least in my case, was normal. Since the old fan clutch was old (105,000), I was used to not hearing the sound it made. Theoretically, if the ac is on, then the clutch needs to work harder to do its job. But I have noticed it does not do it when the ac is off. Just my thoughts.

 

[SCEXPLORER]

Originally posted by MrBean972
The IAC sounds like a logical solution.

I know AutoZone sells the IAC sensor and it was around i think 35$.

I live in Texas and we have AUtoZones everywhere i dunno about where your at.

Just wondering? Do i ask for the IAC sensor or IAC valve? Is it the same unit or are they different parts?

-Ray

 

[AgExplorer]

Just ask for the IAC or Idle Air Control. If they're competent, they'll know what your talking about.

 

[DocVijay]

Did it work?

has anyone replaced the Idle Air Control and did it stop the howling? Please let me know soon, as the noise is getting out of hand. It's OK on the freeway, but in city driving, it drives me crazy.

 

[fastcougar]

This is the sound that I was talking about in my post: "Dead Link Removed". Instead of howling, which is also a great term to express this sound, I refer to the sound as "moosing". I use the term "moosing" because this is a common term used when refering to a similar occurance with the SVT Contour. The solution for the Contour owners was to replace their IAC Bypass tube that goes from the IAC Valve housing to the intake tract. This may be a solution for us as well. I know this because I also own a Cougar, which doesn't "moose", but is based on the Contour chasis. The Cougar's IAC Bypass tube has 3 90 degree bends in it and looks like the tube is stepping. The SVT Contour IAC Bypass tube is more of a direct shot from the intake tube to the IAC controller with only two 45 degree bends. Nobody really knows the cause, but it is believed that the air being pulled at idle is causing a resonance in the bypass tube just before the IAC. Why it only occurs when hot outside is beyond me.

 

[redhat]

Annoying and embarrassing noise - IAC

I’ve been trying to track this obnoxious noise down for a while now – Gumout did not help. As with some of the other posts, my problem appears at idle on hot days – when the engine is hot. The IAC bypass tube may be part of the problem, as the sound has kind of a vacuum leak type sound to it – except that my truck just started making the noise this summer - does the tube need to be cleaned out? If it were just an airflow problem, I would have experienced the problem since new?

Has anyone replaced the tube or the IAC valve? My truck has 80K miles on it, and never did it until this summer. Seems to me that the problem is age or mileage dependant – something either getting clogged, dirty or just going bad (IAC)?

Help!!

 

[Bandit1200]

i replaced the IAC ,the howling is gone ,,got mine at autozone
cost 63.99

 

[fastcougar]

I just realised that the 4.0 OHV intake manifold has a fixed bypass built into the manifold, so the tube is "fixed" and not replaceable. Guess that it is the IAC considering that someone has changed it and cured the problem. Happens so infrequently that I don't know if spending $64 is justified in my case.

 

[SCEXPLORER]

Too MUCH!!!

If you have a SOHC, it costs 99.99 at autozone. Don't know if i want to spend that much to fix a sound. Hmmmm.

 

[DocVijay]

I think it's worth it.

Most of the driving I do is in the city, so I hear the howling every 30 seconds. The $65 is a small price to pay for my sanity (what little is left). I'm gonna go get one today and I'll post tomorrow if it works for me.

 

[SCEXPLORER]

Re: I think it's worth it.

Originally posted by DocVijay
Most of the driving I do is in the city, so I hear the howling every 30 seconds. The $65 is a small price to pay for my sanity (what little is left). I'm gonna go get one today and I'll post tomorrow if it works for me.

WAit!!! I just ordered mine from fordpartsnetwork.com for $48.99. Say your a member of the message board and he'll give you a good deal.

-Ray

 

[DocVijay]

Thanks.

Thanks for the tip. I'll look into it right now.

 

[DocVijay]

IT WORKS!!!

Finally, my Explorer howls no more. I replaced the IAC valve two days ago, and so far, the noise has disappeared. When I put on the new one, I compared the insides of the two valves. The old one was all black and crusty with dust. I guess that was the problem. Hopefully that will be the end of it.

 

[countrymz]

Think about this

All of you guys that have described this problem all have done mods to the intake system. I.E., k&N, kkm, throttle body, mass air sensor. Did any of you ever think that this sound was caused by more air whistling through? Mine does it too and I have K&N fipk, 70mm mass air sensor and a 63mm throttle body.

 

[SCEXPLORER]

Re: Think about this

Originally posted by countrymz
All of you guys that have described this problem all have done mods to the intake system. I.E., k&N, kkm, throttle body, mass air sensor. Did any of you ever think that this sound was caused by more air whistling through? Mine does it too and I have K&N fipk, 70mm mass air sensor and a 63mm throttle body.

Yep i have those mods. Well only the k&N. I think that prob contributed to the volume of the sound but i just replaced my IAC and the noise is all gone too. My old IAC was raelly dirty also.

-RAy

 

[DocVijay]

Thought about that, too.

Yeah, at first I thought that it was the filter, as that seemed the obvious source of noise due to resonance. I tested it by removing the filter and covering the end with a cloth (don't want dust to get in there), but it kept making the sound. As for the throttle body, it doesn't seem like it would cause any noise due to resonance. Anyhow, now that I replaced the IAC valve, the sound is 100% gone, so I think I can safely say that was the problem. The K&N may have helped to let more of the noise out since the factory box is tuned to dampen some of the resonant air noise. Getting rid of that let's more noise out. So yeah I think they all helped contribute, but it's gone now, thank goodness.