Does anyone know what it could be?...engine is stock JDM

 

stock motor? what happens when u give it throttle? does it run consistant? give more info

 

Are there any leaks of any kind, vacuum leaks, exhaust leaks? Is the oil level where it should be? How about the coolant? More details please.

 

OK well sounds starts after car is warmed up
can only really be heard while inside the car
when I popped the hood its hard to hear the sound due to reagular engine noise
When i hit the throttle sound does not increase...can only really be heard when at idle or at a stop light...As far a s leaks I dunno no coolant leaks...vacum i dont think so it idles fine..and no check engine lights

 

oh and car runs fine has all power in the right places along the power band