Reason for the question: When I got the car smog tested recently, the tech said the car was idling so slow the test machine wouldn't register it as idling. They futzed around and did get it tested. I notice in my manual (Chilton) the chart for idle speeds by model year states 370-470 rpm for all 1992 variants, but for '93 to '95 the figures vary between 550-720. The last time I adjusted idle speed I set it to ~450 but that does seem low.

Question: After setting idle speed per procedure, when the IAC is reconnected and ECM is reset (backup fuse) should the idle speed then increase somewhat?
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A properly running VX will idle at 500rpm. It is part of the fuel saving strategy Honda employed.

Rolling to a stop you should see roughly 700rpm idle and then after sitting for a moment the idle will drop to 500.

Double check the idle setting procedure for a VX. It is not the standard Civic process.

 

Thanks! Unfortunately, I only have a Chilton manual which treats all '92 Civics alike WRT idle adjustment.
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@Ryanthegreat1 That's great, thanks. So rpm should come up 180 rpm (420 -> 600, +-50) after reconnecting the IAC and resetting the ECM.My book doesn't reference the "after" rpm.

If it doesn't, it seems likely the IAC is the culprit. (But I am not getting CEL code 14.)
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I Just wanted to comment on the picture that came from that book. I you didn't think many people had that book. I just got to say you're lucky to have it I have it also and it has helped me with my VX many times as I get 800 page book you can every spec you need and repair you need to do to the VX is in that book. That's why it's 2023 and I still have mine and it runs good.
Now I'm tripping on the name that the original post came from, "Ryan the great 1"
Just because he has that book and my name is Ryan and I have that book but I'm not Ryan the great one