At first I thought my ears were just going bad or I was imagining things, but I am pretty sure it is real. I am getting a faint, very high pitched whistle noise from somewhere (I think) in the engine bay. It is usually there, sometimes not at first, and sometimes not when I am accelerating, but nothing consistent. It's not a loud squeal or anything, it just sounds almost like a dog whistle. I know jeeps make all sorts of strange creaks and noises, but this one might eventually drive me insane. Help!

I tried to make an audio recording, but I can't figure out if it is possible to post .m4a files here...

 

Whistle could be a vacuum leak, obstruction in the exhaust or intake. Vacuum leaks tend to get louder when your foot is off the gas..

 

If it's NOT on acceleration, then it's on deceleration. High vacuum.

Check and see that your intake manifold bolts aren't loosening up.

Know how to find vacuum leaks using throttle body cleaner?

 

I've never done it before, but from what I've read you basically spray the cleaner on the suspected line and listen for any idle rpm changes, right?

 

You got it.

 

I thought humans couldn't hear Dog whistles.

Maybe it's a Cat call.....

 

Nah those sound like power steering pumps going bad

 

You sure it's not the wife in the passenger seat?

 

Good point.

Packs of feral dogs following you to a stop?

 

They will be if they hear his jeep along with all his neighbors dogs

 

A Wolf whistle? Wolves are basically dogs ain't they...