i have my AEM intake for about 2 wks. now, at first i get 3-5 more mpg. on normal driving/no heavy foot, but now i'm get 4 mpg less, is this normal. and what's w/ the high pitch whistle.

 

Well 1 good thing about a cai, it gives a little more performance if u didn't know, and another good thing is the way it sounds. But u have to reset ur ecu, i think u disconnect the battery for a while.

 

TL|GTX is right.

Reset your ECU for for 15 minutes (Take the negative off of your battery, DO NOT do so if you don't have your navi codes!)

The intake whistle is normal, a lot of people have it.

 

If you installed the p2r spacer with the intake, double check to make sure u don't have a hole in ur intake

That might be the casuse of the mpg drop, that or you've been gas happy

 

i do notice there is a slit hairline where the space. the installer didn't takes of the old thin piece of space of the oem. do you really need to take that off before the new spacer is install?in the video by San Diago diy. he uses a razer to takes it off.