Like I am just wondering but say if you have such a load on the engine that the ECU fully opens the IAC (Idle air control) but the engine is still not idling at sufficient RPM will the ECU resort to opening the throttle body? like I know that it will likely never happen but say if there is the A/C and for whatever reason there is a really high electrical load and the IAC cant supply enough air to keep the engine idling then what does the ECU do.. Also in manual cars when sometimes the driver does not touch the gas and only lets the clutch up a little bit how does the engine perform that? does it open the throttle manifold to keep the engine idling or just open the IAC as far as needed until its fully open then the engine stops? Or does the IAC supply as much air as the engine can possibly take at idle? like would opening the manifold cause the fuel to lean out too far and so the ECU falls into a trap here.. **NOTE** I am talking about Throttle By Wire systems here, ones where the ECU can control the throttle
