High Idle I have already tried adjusting the idle screw. This did not help with the high idle on my 1988 Honda Accord. Could it be something else?

should be a idle screw on the throttle body. right next to the accelerator cable. also make sure your cable isn't pulled tight keeping the accelerator opened slightly for a high idle

most have idle up solonoid to raise any rpm lost by compressor.. if still too high when compressor is engaged then that may be problem... is adjustable

try turning down the idle via the idle adjust set screw (usually on the carburetor base). if the problem persists after the engine is warmed up, there may be an issue with the automatic choke. also check the throttle linkage by disconnecting it to see if it is holding the throttle open when connected. if this is the case, you may need to adjust it or find a slightly longer cable.

Carburated engines of that year may have an idle screw adjuster. You can see the screw from the outside of the carb. If so, try adjusting the carburator with a screwdriver. Unlike fuel injected Engines they can be manually adjusted.

THE DISTRIBUTOR WILL CAUSE THIS PROBLEM IN A HONDA TRY A KNOWN GOOD ONE .

find your cable that goes to your throttle body and look for a screw on a fixed plate, the screw should be touching a cam leaver for the throttle butterfly. if the is no screw it may have rattled out and you may have lost it. Or the idle is done by the computer i in the case you may have a fuilty sensor or computer.

turn the idle screw down on the carburater

if its a carb model you might need to strip and refurb the carb if not buy a second hand one they are pretty cheap or it could be a choke problem

Should be an idle adjusting screw on the side of the carburator that you can adjust to move your idle down.

-Captain Jake

)The fact that thge engine idle fluctuates when it is cold indicates that the Fast Idle THermo Valve is out of adjustment.
This valve is located ot the front of the intake manifold on the driver's side just below the accelerator cable. To adjust it, wait until the engine is cold (best to do it first thing in the morning).
Remove the two screws holding the cover on and start the engine. There is a brass needle sticking up through a plastic ring that has two slots in it. With the engine idle fluctuating, use a thin flat blade screwdriver to SLOWLY turn the ring CLOCKWISE
until the idle stabilizes. Once done. put the cover back on withg the two screws and you should be done.