Update: Today i decided to open up the throttle body and inspect the condition of the IACV as a DIY. Though I have never seen how a dirty TB looks like, but this TB appeared to be in a pretty bad condition. I didn't take the picture of the TB, however I am attaching the pic of the the dirt and debris that got off of it by just a single spray of the Carby Cleaner.
And the inside of the manifold is a horror story as well. Below are the two pictures of what was inside. I didn't knew what to do with this and how to clean the inside of the manifold, so i just sprayed a generous amount of the carby cleaner while the engine was off, I knew i screwed up here. But still i'd like to correct it, yet i don't know wht to do.
Here the pics of the IACV before clean-up. IACV was thoroughly cleaned with the carby cleaner using cotton buds, brush and cotton cloth. And to prevent lint from settling in, i used blower to dry it up. Same was done with the TB.
Results: Nothing has improved, things have become worse :P. Before this, idle rpm(warm engine) was 700 and now it's 850. The cold idle used to be 1200 and now it has risen to 1500!
Even though the problem was the initial fluctuation in the idle rpm, but the idle was pretty smooth. However, after my ''panga'' today, the idle has become quite rough at 850. I haven't driven the car yet, I am just noticing the idle rpm. Maybe if i drive the car, things might get better?
Before this, the initial fluctuation was from 700 to 200 and now this fluctuation has moved to the bracket of 850 to 500.
Again, none of the sensors were tempered with, only grips were taken off and no adjustments were done. Only IACV was cleaned.
Awaiting response, from the experts!