I fixed the howling sound!!!

[KJB]

Lately my explorer has been making a howling sound when it's idling. Last night I was checking around for the cause and I got to looking at the Air Idle Control Valve. This valve is a solenoid valve with a black button looking thing that is mounted on the side of the intake manifold. The black button is actualy a breather and when I opened it up I found two 3/8" diameter felt filters that after 203,000 miles were clogged solid. I removed the filters, snapped the cover back on and the noise is gone!

 

[Heath]

Don't you think that you should replace the filters???

 

[KJB]

I guess they're were there for a reason. But the hole that they cover is less than 1/8" in diameter and there is a plastic cover on the breather. The amount of air that goes through it isn't going to amount to much when you consider how much goes through the air cleaner.

 

[Robert]

But the filters might be there to prevent small particles from getting into your IAC valve which could cause it to get stuck at some idle speed you really don't want it to be stuck at.

 

[jwild4x4]

My X is currently making a howling sound too (like blowing over a beer bottle) from the intake area. I read your post and went to my shop manual to find the IAC. The one pictured in my manual has two screws which secure the valve to the mounting bracket, which is mounted to the manifold by two bolts. I have a 95, V6, 4.0L, and what appears to be my IAC does not have the two screws which will allow me to remove the IAC valve. I would love to fix my harmonics problem, and would like to know how to remove the IAC valve to check and clean it... Thanks

jason