Guys I need ur help I have a 03evo on stock boost and stock setup but the bov is off an mr and it chirps in boost and in high vac some say it is surge if it is how do I fix it?? And also the car has been doin this since I bought it and it's peaked at 18 psi but it peaks at 11psi what happened help plzzz thanks

 

i have the same bov, ur fine, when not under full boost the bov wont open completely, itll make the noise ur hearing, ur fine, dnt worry about it

 

it sounds loose. check the connection from the bottom and side of the BOV. when mine was loose it would flutter. also seems like you may have a boost leak from somewhere. check all your piping (licp/uicp is notorious for popping off) and vacuum lines

 

Are you saying it used to boost 18 psi and started boosting to only 11 psi now? Does it feel like you lost power?

 

A stock evo should boost 19.5psi if Im not mistaken, you've got a major boost leak!