I have a 95 Civic EX Sedan w/ D16Z6 and 5spd.

Some details about the state of my car before this problem:
Twice while driving on cool rainy days (70deg F) my CEL came on while driving but would go off when I shut the car off and started it back up after coming back from the store. (checked the code today its 43 fuel system problem) I also have experienced that when driving the car and getting it up to operating temp then shutting it off and trying to start it within a couple minutes it would start then die, I would wait no more than 2-3 minutes then start it up again and it would run fine. At no point has this car died on me while driving either cool or warm.

I also have a fluctuating idle (1200-2300 RPM) when the engine is cold, once the temp gauges gets to the normal spot below half the idle stays steady at 700 RPM. I suspect for this issue I just need to clean or replace my FITV or IACV.

Todays problem: It is cool and rainy again, (today is when I checked and found it is code 43) while doing some other work on the car I decided to pull the under-hood back up fuse (the 7.5A one to clear the CEL codes) to see if the code would come back. I had the fuse pulled for probably 10 minutes, I plugged it back in and started the car. Did the usual fluctuation until it warmed up then steadied out, I revved it up a bit and it sputtered while revving then the idle dipped really low and it died (this has never happened before) then wouldn't start back up.

Also noticed a bit of dark grey smoke coming out the tail pipe which never happened before either. While it was warming up I smelled the exhaust and it smelled like fuel (car doesn't burn oil or coolant) although it has always smelled rich (bought the car with no cat) and the O2 sensor bung is welded into a little cross pipe between the two pipes that come out of the aftermarket header (no bung in the header)

Other than the issues I listed above the car runs strong, good pull no lagging or misfiring and no other CEL codes. the whole dizzy was replaced by PO right before I bought the car a month ago.

Any thoughts on what I should look for? Do these ECMs have adaptation values that I cleared by pulling that fuse? I am waiting for it to cool down right now to see if it will start.

 

Well I already figured it out. Went out and cranked it for a bit and noticed the CEL came on while cranking. Checked it and got code 15. Looked under the hood and the yellow power wire (i think?) to the dizzy was broken. Fixed the wire and it started back up.

As far as my hunting idle goes does it sound like cleaning the FITV and IACV will fix it? Don't have vac leaks and the idle is fine once the engine is warm (does take maybe 15 seconds to return to 700RPM after blipping the throttle when warm)

 

This^ is where to start.