Im having a weird issue with my Civic. When I start the car up it idles extremely low, like real low. Than I give it some gas and it holds at like 800 rpm. Than when I go to drive and I shift my car down to neutral, the car will either drop down to around 200 rpm and surge back up, or it will just die out. I cleaned the IACV, but I think its a problem with the TB

 

There is a screw on the upper part of your throttle body that you can adjust out with a flat head screw driver to raise your idle. How i took care of my surging idle on my del sol with a d16z6 was chip and socket my ecu and burnt a basemap on crome (which can be downloaded for free) and adjusted my IAC through the crome program. In total cost me $120 and now I can tune my car to my needs with Surging problem solved.

 

Target idle is sweet!

Op, I doubt there's anything wrong with your tb. But it wouldn't hurt to make sure the throttle stop screw that catches the wheel that the throttle cable goes through hasn't backed off, allowing the butterfly to close more than it should. The throttle stop screw should never be tampered with btw.

 

Where is the throttle stop screw located?

 

Bottom right in that pic. Under the wheel that the throttle cable connects to. See it?

 

75 % of the time cleaning a HONDA/ACURA IACV will not help it!!!

So hit up a friend and try his/her iacv! SOHC will work. long as its not a DPFI system.