I got a 1995 honda accord lx 4 cy, non-v-tech engine, that has a bit of a rough idle issue. I've had it for quite awhile. It drives fine as runs smooth and a pleasant drive and gas is ok getting 19-20 because I have a lead foot.

Plugs, wires, transmission flush, oil change done in April of this year, air filter replaced 6 months prior, fuel filter replaced a year ago.

Anyways long story short, the compressor went out about a year and half ago and ever since it was replaced, the engine has had a rough idle.

I live in florida, during the day if I drive, I use the A/C, the engine idles rough. If I turn it off, it runs fine as in smooth, idles good. At night if I use the headlights, the engine runs rough, but if I use the A/C too the engine idle goes to ****, not enough to stall but man, it shakes like crazy, feel's like I have a dead cylinder.

I have a tach in my car and the engine idles around 550 with no A/C or Headlights/running lights.
With A/C on, it idles around 350-450, and with the headlights/running lights on it drops to 300 and if air is warm or humid as **** 250.

Here's the funny thing, when I drove it from florida to new york in may of this year, all my rough idle problems went away as we headed north. I think I noticed it around Virginia or North Carolina and it ran beautifully, no rough idle, nothing and we had some pretty long traffic lights, just nothing, idled perfectly.

So my guess I have **** air quality or something is not set right or has gone bad.

Now the question is what's the stock manufacturer idle suppose to be at?
What can cause a bad or low idle?

 

I have the same car. And same issue sorta. Any time I turn something on in the car head lights, ac.....etc the idle drops. I beleive it has something to do with the fact our idle is electronicly controlled . Every time my subwoofers hit my idle drops and almost dies. U can try setting your base idle properly first and make sure the throttle body is clean and also the IACValve on the back of it might need cleaned. Both the base idle project and IACValve cleaned can be found in the sticky threads with detailed descriptions and pictures. For me none if this helped. I live in PA so I never use the AC but I just got used to it I guess. My subs make the idle go crazy but ive never had the car stall. Came very close alot of time but never stalled. I beleive wr only have 90 amp alternator on our car. Im not sure thou. Which 90 amp isnt alot. And AC pump pulls alot of power. When u first turn on the headlights or AC does the idle go back to normal after a while ?

 

Does the power for your system come directly from the battery? If so, that bypasses the fusebox and ELD. The ELD (electrical load detector) measures changes in the load on your alternator, and allows the idle-control system to anticipate the load of the alternator.

Besides that, check out a thread in the DIY section about setting the "BASE" idle.