I used to have RM racing CAI, the problem is when I acceleration between 1000-4000 rpm shortly ringing noise from CAI or throttle body I don't know which one. After a month I bought weapon-r CAI make same noise like RM racing CAI.
Have anybody have any problem with CAI like mine.

 

I don't think the CAI caused the ringing sound. Definitely something else. Like you said after using another CAI, the ringing sound is still present.

 

Do you still have the RM racing one?? I have the RM racing HAI and would like to know if you will sell the lower half to the piece?? let me know

Thanks!!

 

I will like to sale it, but my intake pipe got small dent on it. just on the long pipe.