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89 accord won't idle

I just got an 89 accord LX with 153,000 miles on it. The engine dies at idle whether its warmed up or cold. Does it need a carb rebuild, or could it be one of the many associated systems?

Yes. It could be one of the many associated systems, or it could need a carb rebuild. I suggest you purchase a service manual and start following the diagnostic procedures for incorrect idle speed. Or take it to a mechanic.

The first thing to check is the anti-diesel solenoid.
This is a small solenoid on the carburetor body that has a pigtail wire connector on it.

Disconnect this, turn the key to the RUN position (engine not running) and lightly make and break contact with the wire connector a few times. You should hear the solenoid click each time.

If not, either power is not provided to the solenod or the solenoid itself is faulty.
(This solenoid shuts the idle circuit in the carburetor completely off when the key is turned to the OFF position. This is done to prevent engine run-on; or dieseling as it’s called.)

Great, I’ll check that and let you know what happened.

That solenoid is working, is there anything else I can try before I swap carbs? BTW, the car was idling sort of in park or neutral, and would cut off when I shifted into reverse or drive. Now that the air cleaner is removed, it won’t even do that. Does that have anything to do with it?

Idle problems are usually the result of a faulty idle air control valve (IAC). I assume your accord has an IAC or something that performs the same function.

There is no IAC valve on this car. It could be junk in the idle passages of the carb. You can carefully remove that anti-diesel solenoid and spray some carb cleaner in there. The other possibility is a vacuum leak making it too lean.

Sort of idling puts a different spin on it. When the solenoid I mentioned is inoperative there are no ifs, ands, or buts about it; the car will instantly die at idle with no sputtering at all.

Since it at least kind of idles it boils down to the following.
Vacuum leak (easily checked with a vacuum gauge). Carbureted Hondas of the 70s/80s were some of the most vacuum hosed and control solenoided vehicles ever made. A vacuum gauge won’t find the leak but will let you know instantly if there is one and can aid is tracking it down. (Pinching off vacuum hoses one at a time with a pair of needlenose pliers and watching the gauge)

Idle too low. Make sure it corresponds to what is listed on the underhood sticker.

Dirty idle circuit in the carburetor, clogged air bleed, etc.
Before buying a rebuilt carb (they’re expensive) you might try a few backyard methods of clearing the problem up. Hokey as they are, they sometimes work.
With the top of the air cleaner off and the engine idling, take an old towel and muffle the top of the carburetor while revving the engine by hand with the carb linkage. Remove the towel before the engine dies and repeat the process a few times. This can clear out an air bleed obstruction in the upper carb body.

Remove the idle mixture screw and squirt a healthy shot of aerosol carburetor cleaner into the hole where the screw was. If possible, try to use an air gun to force compressed air into that hole. This can clear up a dirty or obstructed idle circuit.

I’ve cleared up a few carburetors over the years by doing nothing more than the above so it’s always worth a shot before spending money on another carb.

(One other thing to consider is that the ignition timing may be retarded too much and can lead to problems like this.)