Im using s90 on civic b20b but now getting prob on unstable idling n heard many user facing same problem bcs of vacum leak. Some said using 1gen S90 throttle body not facing idling issue. Some of bengkel said S90 itself prob ( most my frenz using on cibiv b series).

I was tried some method to get stable idling like TPS adjust, Iacv clean n etc. no check engine but still getting prob. 1 more wat the diff cooper butterfly wif crom butterfly? Any diff?

Try getting others brand as Skunk2...