1998 Kia Sportage Humming Sound...

[OptimusGeorge]

I have a 1998 Kia Sportage and on Wednesday last week, it developed this weird humming noise that happens when I accelerate. The more I accelerate, the more noise is heard. If I'm going 65 MPH and I take my foot off of the gas pedal, it decreases and then goes away even when I'm still going about 60 MPH. It happens with the amount of time I take my foot off of the pedal. It doesn't sound like gears grinding or anything like that... it almost sounds like wind noise... it's really weird.

The hose clamp for my air intake fell off some time lately, could this be causing some kind of air noise? I'm also missing some screws to the air filter housing. (What type/size do I need to replace these?)

Any help would be much appreciated!

[andrew28]

My guess would be your fan clutch. I believe these come in an assembly and aren't too difficult to swap out. To the best of my knowledge you have to go through the dealer to get one and I think they are around $100-$150 for the part.

[tomiro]

My 2000 has the same thing going on. It's the fan clutch not releasing so the fan spins faster than normal instead of slipping as it should. My wife says it sounds like an airplane.

There are two ways the clutch can fail. It can slip all the time and not cool the radiator, or it can stop slipping and start humming.

The later, though a little loud, isn't as bad of a situation. It just moves more air and actually keeps things cooler. The problem is in cold wintery weather the blades can break because of the wind force and damage the radiator.

I'm lazy so will probably change mine in October. I'm also curious if they can be fixed but from what I've heard the fan should be changed at the same time. In fact Kia only sells the entire fan+clutch assembly, you can't get just the clutch.

Here is where I will probably get mine. $85.84 including shipping.
http://catalog.drivewire.com/drivewire/bas...ry+Fan+Assembly

[OptimusGeorge]

Thanks for the information tomiro. I don't know if I'm going to let my ownership of my KIA last until October, but we'll see. I'd probably do the same thing if I'm going to keep it. It's up for inspection in August. I'm going to take it in as soon as possible to see what the damage will be this time around.

[DSHornet]

The fan clutch operates on the temperature of the air flowing through the radiator. As the weather warms up, that temperature goes up and the fan runs more. If the fan causes the whirring "fan" sound (for want of a better word), and them decreases at higher speeds, it's working right.

Often, if you accelerate heavily, as in going on an entrance ramp to a major highway, you may notice that the fan sound decreases in pitch as the engine noise increases in pitch. This is normal operation. Don't worry about it; the fan clutch is working okay if this happens.