Idle speed can be modified but I am not sure how. When I was learning to drive, my Waggie had decent rpm but I was learning, so it kept stalling. When I mentioned this to my mechanic, he increased the idle, so the car never stalled even if I was not accurate with the clutch.. Much later, when I was more used to the car and driving, he dropped the rpm again.
With the Baleno, I have seen it drop under 600 rpm several times. Case in point this snap I had taken when driving some time back
Today with the car in parking, I was able to get this output from the OBD scanner. Lowest rpm is about 620 with the aircon on in ACC. With the aircon off, the car idles between 640 and 660rpm. Yes, its weird that the idle is higher without aircon than with. Also, this was in the middle of the afternoon but with the car shaded by buildings. Outside temp was showing 26 Deg C on the MID and inside was set to 24 or so.
A small thing I noted- with the ACC set, the fan runs at very low speeds and idle rpm remains low but if you raise the fan manually, idle rpm rises. Not sure if its related.
Another thing- I always felt suffocated in the car with the aircon in ACC. Cool but suffocated. I like more air movement but at higher temperatures, even in my Swift. Yesterday night on the way back from work, I drove the air at a higher temperature (26 or something) but with the fan running at a higher speed manually and it didnt stall or brownout even once on level roads. Again not sure if its related
I will again test the car with the OBD for idle rpm in the evenings
Ameyam