93 Accord 4cylinder
In the last few weeks I've replaced the starter and rewired the cooling fan.
Now I need to figure out what is up with the idle.
The symptoms are pretty classic. As the A/C cycles on and off the idle goes up and down, to the point where the engine is going so slow that it is bucking and seems certain to stall but doesn't quite do it.
I need to know where to start. What are the most likely culprits?

 

Sounds like you need to Clean your IACV valve. There is a good writeup in the FAQs. You could also replace your spark plugs, plug wires, distributor cap and rotor button. Then you can also test your ignition coil to make sure it's functioning properly. Clean up your battery terminals and connectors, make sure all grounds are clean and tight. Replace your air filter and have your valves adjusted. That should just about cover it!

Someone please add more if I missed anything.

 

Mid Life Crisis,

I would like to also add that you should check to see if you have a vacuum leak anywhere as this is another catalyst for rough idle. Inspect all of the clamps on your intake piping and if they need to be tightened then do so. I have had erratic idle issues on some of my cars in the past and more likely than not a vacuum leak was the culprit.

 

Thank you. It looks like an IACV cleaning and vacuum line chasing is in order for starters.
The battery wiring is good from troubleshooting the starter issue.

 

Start with a tuneup.

 

I'd start with checking history for a tuneup. Check your front motor mount (the rubber often breaks).

Simplest thing to do is a throttle body cleaning. Remove your intake from the throttle body (flat head screwdriver) while the car is off. Spray some carb cleaner in there. Use a bottle brush or rag to wipe out your throttle body (you can manually open the plate inside to clean it out). You may have a tough time getting it started back up initially but it should be a little smoother

 

I ended up getting a heart procedure done so I'm not able to work on the car for a few days, but I'll update with results when I have them.
Thanks to all who replied.