i get a ticking from my car when it sits for a few hours,as soon as I step on the clutch pedal it goes away.......I am thinking TOB???????
sound is coming from under the car is my best guess
a guy up the street just bought a used s197 gt i heard the same sound coming from his car.

 

I had the same thing happen a few weeks ago. Check to see if your defroster is on.

https://mustangforums.com/forum/2005...lternator.html

 

The same thing is happening to mine, w/ no defroster. I think its a bad lash adjuster. Which I've been meaning to fix it, but I think you've gotta pull the rocker arms. Which I think involves having the special valve spring compressor tool. Ford and Rotunda...what a racket.

 

its not the ac compressor lol ! and its not comming from the heads either, its more like a rattle, had my uncle look at hes a mechanic he also said it was the TOB