After adding the following mods on my 03 STi, the CEL light came on. The fault code was too lean in cylinder No. 1. After getting the car back from it's remap the CEL came back on after 15 miles. Is this something that has been caused by the APS CAI or the other mods and should the remap have resolved this?

APS CAI
GT Spec Headers and Up-pipe
TD 05/06
3 Ports Post Solenoid
3" Turbo Back H&S System (Replace a 2.5" TSL System)

Cheers

Marc