ok i installed a home made intake on my eco and im getting a check engine light and when i floor it, sometimes my car hesitates for a second then pulls, i cant figure out why? i have no open holes in the pipe or anything, breather filters is on, air sensor is securely in (this is on a cobalt), im thinking maybe the air flow is restricted somehow? its a 3 in cone filter, not k&n but same one i used on my cavalier and had no problems with it....i just cant figure out why its doing this...any help is appreciated

Start with the tried and true methods, begin by making sure all your harnesses are fully plugged in, your MAF is not backwards, etc. Easiest check would be to pull the CEL code and go from there.

It's more than just an air restriction. For a check engine light to be on, you've failed some sort of airflow rationality diagnostic. If I were you, I would double and triple check for vacuum leaks somewhere in your intake plumbing. 99% of the time that's the cause.

Otherwise, reevaluate your design. If you have the MAF too close to the air filter, you may not be giving the air flow enough time to 'straighten out' before the MAF, causing inaccurate readings.