Ex making the weirdest noise!! Help!!

[Sethro]

On my way home from work today, on the highway, I hear the loudest noise, outside the truck, sounds like an electric motor, higher pitched whirring. Constant for a few seconds, then stops, then constant, etc. No idea what it is. Thought I was crazy, did it again tonight on backroads. I haven't the slightest clue what this is, can someone help quick???

 

[cjbarron5]

try cleaning the iac first

 

[Mbrooks420]

If the IAC has ever been replaced it may not be cleanable. If you have to buy a new one they are about $30. After a while it will make the noise more, and eventually start stalling.

 

[TPLYNCH]

Do you have the automatic suspension leveling system?

 

[DeRocha]

Is it the AC clutch locking an unlocking? The AC will come on (automatically) in any of the defrost modes (without actually pressing the AC button).