Yep. Sounds like a completely fouled or disconnected MAF. Pull it out, give it a good look, clean it if needed, inspect the plug in connections to make sure it is seated properly. Also trace the wire harness to make sure it did not get damaged or pinched during your intake mods. This should be an easy fix if you take your time and follow a process of elimination.
FYI: disconnecting the battery will always turn off the CEL and erase the error codes but it doesn't erase the problem that is causing the codes.