Haven't had a ton of seat time quite yet, to monitor AFRs and IATs, but I've noticed the same. I hear steady little hisses as the IAVC opens and closes to try to keep the idle smooth with that cam too. All in all a nice piece with great fit and finish for a fair price.The exhaust came out very nice, I also have the hybrid racing intake and noticed it makes a very pronounced sound as soon as the TB starts to open. I dig it lol. Iat stay very close to ambient temps when moving as well.