I got my car half jacked back in April, FMIC stolen, they went under the hood but didn't take anything..Ever since I got the car back with a new and bigger intercooler, the BOV has been stuttering between shifts like "tsk tsk tsk tsk" as opposed to an even "tssssss". I checked all my hoses, everything is hooked up together properly. I tried untightening the BOV spring several times, it's just as if it refuses to open when the throttle closes.

Could this be an indication that the BOV is shot and I need to replace it? Or could it be something else..?

 

You should try calling the manufacturer of the BOV and ask them the proper way to test that the unit is functioning.

I would imagine it would be to apply positive rpessure or vacuum somehwere on the valve.