Weird Noise

[94ExplorerSS]

I have been getting this weird noise latley comming form the engine compartment, when it is as idle. Its kind of a humming "whirring" noise, but when the a/c is on sometimes the noise stops. WHat is this? Is it he compressor or sumtin?

 

[mrboyle]

It could be one of several things. It could be the bearing in the A/C compressor clutch, it could be a bearing in the alternator, an idler pulley or even the belt itself.

 

[Alec]

If it is very very loud, it is the IAC.