Electronic Control Module (ECM)

Question

Is there a way to tell if the "Electronic Control Module (ECM)" is bad & giving off false codes? I have several codes P0133, P0340, P0335, P1372 for a 2003 Hyundai Sonata. Several of them point to same possible causes. Issue: Car drives fine, then hesitates & mainly while waiting at lights the car will idle low & stall out, have to wait after several attempts, I can get the car to start. The check engine light doesn't come on (it does work), just started coming on very briefly. These codes were in in the history. The sensor appears to be good & replacing it anyway, starter, battery, alternator is all good, timing belt was replaced. Can't seem to find any bad wires! HELP