humming noise video

Again, remove the belt. It could be a powerstearing pump, water pump, altinator or the such.

The bearing may take a while before it whines, as it has to heat up. It must be dry, and then when it heats up it starts making noise. I belive thats your problem (most likely the ALT.).
 
Just in case myself or someone else (ie christie) has this problem with the IAC, what exactly is wrong with it, and how do you fix it? Is it a seal problem or just a bad IAC, need some more info on whats actually going wrong. I am pretty curious about whats going on, never heard another GT do this before. :shrug:
 
svttech76 said:
IAC... i have heard this EXACT noise out of the iac before..
I agree. I my Mazda B4000 was making the same sound. It turned out to be the IAC. Mine would really humm when it was hot out. On one video when you hit the throttle, the noise went away. The computer cycles the IAC to go "closed" when the throttle is open(svttech correct me if I'm wrong). Get that thing replaced before winter. My truck wouldn't start one cold winters morning. I removed the IAC and let it warm up for 15 minutes. I put it back on and the truck started right up. Pearl02.
 
So, was it the IAC?

I just installed a 75mm Accufab combo and I get this howling sound at idle when the engine is nice and hot. It doesn't do it on short trips but after driving around for an hour, it will do it at idle. Raising the RPM makes it stop.

The videos have the exact sound mine is doing. I describe it like making a champage glass howl.
 
Just in case someone else experiences this... here's how my story ends.

I removed my IAC and cleaned it. After reinstalling it, the howling went away. Great! A few weeks later, I noticed it was still howling but a lot less. So I removed it to clean it again. But then it wasn't really dirty. I sprayed it with carb cleaner anyway. When I reinstalled it and went for a drive, it howled a lot. Anytime my foot was off the pedal, it was howling loud. Just like in the video csledd posted. I was like wtf?

So I figured it wasn't a matter of being dirty. I thought maybe it was how it was seated. So I loosened the screws a bit, pushed the IAC upwards, then tightened the screws. Now it is as quiet as a dead bird. No howling at any engine speed.