this happens pretty often with my v6. i have a 99 mustang, everythings pretty much stock, well over 120,000 miles on it. while im driving i notice a ticking noise coming from what sounds like the engine. its not that loud, but it is noticable. heres what has me clueless. it stops when i press the clutch pedal SLIGHTLY. like maybe 1 centimeter, barely any foot strength, just a little bit of weight on it so that the clutch isnt even disengaged. i dont know what it is. it does this when i am in neutral , and while im driving at cruising speed. any ideas? thanks in advance.

 

exhaust leak coming from the manifold? hear about this problem quite a bit with the 99-04s. the good news: heres your excuse to upgrade to longtube headers!

 

If it makes the noise when idling/neutral, pop the hood and take a look around (listening for the noise). I've got a throwout bearing squeal on my car that behaves the same way (doesn't make the noise when the clutch pedal is depressed, even barely). If it sounds like an exhaust 'tick' then it probably is ... take a look around & have someone else give their eyes/ears a chance to catch it as well.