I'll try to keep this short! I have 94 Civic. About a year ago, I had this problem where my car would idle very low, so when at a stoplight, it would die. Then it wouldn't start right away, I'd have to wait about 20 mins. Took it in, and all they did was turn up the idle, saying they couldn't find anything else wrong. The car ran fine for an entire year! Now I'm having what I think is the same kind of problem! 1st it wouldn't start. It acted like it was out of gas even thought the gauge said I still had 1/4 tank. I put gas in, it started right up. Today, same thing, but this time, after putting gas in, it wouldn't start for about an hour. Now I can get it to start, but it idles very low, about 500, and will die if I take my foot off the gas! Like everyone else, I have a cash flow problem, so any ideas that keep me from replacing a ton of stuff would be SOOOO appreciated!!

 

So this happened last year around the same time frame too? I've heard that the heat(in the summer) could have an effect on the Main Relay causing the car not to start for anywhere from 5 to 30 minutes..that's the 1st thing I would think of if it's been a year since it happened. You can get a new relay or fix it yourself(google "main-relay-fix+civic").

Also...when was the last time you cleaned the throttle body or even put an Carb & Fuel Injector cleaner in the fuel tank?

 

Your idle problem sounds like a classic IACV problem (idle air control valve). Search the forum DIY section and there's a thread about cleaning it to fix the issue.

I'd also agree with the main relay theory, it's pretty common. When it wont start, turn the key to the IGN2 position (right before you turn it more to start). Some lights should come on in the gauge cluster and you should hear a low hum from the back seat area. If you don't hear the low hum (fuel pump priming), its your main relay.

 

Or, here:

IACV fix: https://www.hondacivicforum.com/foru...ad.php?t=62836

Main relay fix:http://www.tegger.com/hondafaq/mainrelay.html