just installed my alta cai and i have a 15% pulley, my consumption meter is saying that I am getting way less mileage than before and I dont know why. Is it because of all the extra air going in? I know it could be my driving but I mean it went down a lot. Has anyone else noticed this?

From what I've read, a cold air intake should have the complete opposite effect. If you don't see a boost to gas mileage then it should be about the same. How much is "a lot"? I've hit low 30s when taking longer trips on the highway, but tend to stay around the high 20s with my half-city/half-highway commute. How big of a drop are you talking about?

like I went as low as 16 at one point and I dont know why, I never went that low before and I still havent hit 30 mpg ever :( but it never went this low till I put the alta intake in

With that big change in MPG I would suspect that that vacuum line came loose. Double check you installation. A CAI should be beneficial to gas mileage.

A CAI should get you a slight mpg gain....a pulley the same....but with the newfound power and sound...folks tend yo become leadfoooted....that and I bet you are running your ac tons more now in the heat....

16 is really low based on my own experience. I've never seen anything under 25, on my CVT, and it's only improved with new spark plugs and performance mods... Even with AC/heat on, driving aggressively, 16 seems crazy low.

Have there been any performance issues?

I would take everything I installed out and go back through the installation process just for a sanity check.

i never use AC unless im on the parkway

Try a new tank of gas. I got some crap gas a few weeks ago an it really messed up my gas mileage. New tank and i'm back up to normal.

Just a thought

Driven even moderatly hard....an S (gen1)s a low 20's/high teens mpg car...
Some do better...heck I average 30 mpg...sometimes 32 on the highway...little traffic....but mid 25 is normal... Lower in traffic or getting aggressive...18-20 would not be uncommon....if I had wide tires or heavy rims...bet 16 would be about right....
Still....check you connections.

this is so confusing! My connections are fine, I only use sunoco or shell gasoline, I changed all the fluids in the car, I don't know what I am doing wrong. This weird drop in mpg is puzzling