chicklet

So, i have been having this problem with my car. It'll idle poorly when it firsts turns over then after a little bit of time, the check engine light comes on it stops that. So it falls into a fail safe mode for it. But I'm trying to figure if its the IACV or the mass airflow sensor. Its a B18A1 engine and I have taken apart the intake all the way up to the throttle body and cant find the MAF (unless I'm just missing it). But please help