curious starting issue

OK, 91 CIVIC DPFI.
as of about 2 weeks ago, she started doing that goofy "start - stall" thing. will start fine in the morning, then, during the day, almost destined to start-stall, then start and run no problem right after.
from what i read, it is main relay.
so i replaced it saturday.
i have exactly same issue. starts fine in the morning, drives fine. when parked, either at work, or at gas station, or whatever during the day: 1. will start and stall. 2. will start and run no problem right after 1st stall.
new wires, iridium plugs, new fuel filter/air filter, religious maintenance, good gas only, cleaners added routinely to keep it all running clean.
no error codes. even new gas cap.
ideas? sort of getting on my nerve, as i drive places, and don't want to get caught somewhere out in woods because of this.

i would test your fuel pressure, and when it wont start or run see if you are still getting spark while this is happening... could be a bad ingnitor or possibly a bad fuel pump... do you hear the pump turn on when you get the crank but no start?

well, it's been what - 3 days since i posted and 5 since i replaced the relay (btw, i re-soldered the OEM one).
it looks like ECM took its sweet time to recognize the new relay. about around sunday afternoon.
she still cranks - well, it's 184 000 miles:naughty: - a little bit too long to my taste, but that's it.

i think i found the cause to that issue that i had.
9 days down the road, i feel it is safe to come a conclusion, without jinxing it badly.

i did not mention this in my previous post, but when i was replacing the main relay, i also cleaned electronic air control valve, one that controls idle.
ever since i had this car, it just plain always gave me that gut feeling that idle control is not working well.
so, i removed it, and fair enough - it was full of soot and water. it is a curious device. a 2 chamber piece, with chambers not connected.

one is apparently either doing nothing, as it has 2 tubes connected to throttle body - but when i disconnected them, there was no antifreeze or anything else coming out of them. yet, that small chamber was filled with water pipe type sediments - gray solid sediment. took some scraping to remove it.
the other chamber has a harmonica looking piston in it, with a dime sized metal screen on one end. i am assuming, that is the valve itself that controls air flow to the throttle body. screen was half covered with soot, harmonica was basically black either. good few shots of carb cleaner took care of all that.
also, i re-sealed gaskets with blue silicone.
as a result, NOW i can definitely tell that idle control is working, as at a start up, when engine catches, i release the key, and rpms want to drop down(stall previously) - there is definite pick up following, and then engine runs fine.
i guess, always trust you gut feeling, he-he.

btw, i have 50/50 Royal Purple/Honda ATF in trannie now. so far...