So I have been dealing with idle issues on my 93 honda del sol since the day I bought it. I think I finally fixed it with a new FITV but I decided to be thorough and go ahead and clean up the IACV. When I took it off I noticed that between the IACV and the throttle body there was a piece of paper. I'm not sure if the belongs there or not but it looks like some random piece of paper put there to block off the IACV. I didn't wanna mess with it since it was running fine but I just wanted to see if I should remove it or what is actually supposed to go there.

Another thing I wanted to ask was about the ECU and CELs. I've had this CEL since I bought the car but finally got around to pulling the codes. When I got to the cable I noticed that it already had a paper clip left in it from the previous owner. I took it off, started the car up then turned it off and shorted it again to see if it would give me the code but nothing came up. The light came on again without blinking. I reset the ECU and took the car for a ride and the light remained on, no change. I know that the engine isn't the original one, it is a d15 now so I don't really know how that affects stuff especially the ECU and CELs.

The last thing I want to ask is what sensors should this car have? It's probably a dumb question but I am just getting into cars and don't have much experience. I noticed there was a cable leading to nothing near the radiator area. I don't have a camera on me to take a picture but a list of the sensors would be good so I can look for them one by one to make sure everything is there.

Sorry for the wall of text and possibly stupid questions but I really want to fix up this car to the best of my abilities. Thanks!