'89 Accord Lx

[Karhoot]

Having a bit of trouble figuring this one out. Got an 89 accord lx. It diesels when shutting her down, and sometime sputters when idling at operating temp. Idles at 1200-1600 or at 800-1000. How would I know when I need to adjust the carb, or adjust timing. Discuss and share ideas fellas! :-)

[Legend_master]

I'm not the best carb tech, but that sounds like the carb may need a good cleaning or rebuild.

[Dr_Snooz]

I saw this thread yesterday and let it go so that the carb experts could weigh in. It never fails. When I wait, they never do. When I try to help, they always come in later and tell me how I'm wrong. Sheesh!

There should be a solenoid on the carb that closes at engine shut down to prevent run-on. Download the manual from the wiki: 1989 USDM Honda Accord Factory Service Manual and you can probably figure out which one it is and how to test it.

Also, like Legend_master said, a dirty carb can also be plagued by rough running and run-on, so try a bottle of injector cleaner at your next fill-up and let us know how it works.

[g.frost]

As Dr Snooz said, the Primary Slow Mixture cut off valve should stop idle fuel delivery when the ignition switch is off. If your idle is at 1200+ rpm though, the fast idle unloader is holding the high idle (or adjustments are messed with) ....still, fuel delivery alone should not cause run-on after the ignition is shut off. Dieseling requires something to ignite the fuel besides the spark plug. That something is usually carbon deposits hot enough to ignite.
Sputtering when warmed up... is it running rich? (this will cause carbon deposits to build fast) Run some PEA fuel system cleaner (like Redline SI-1), and check the fast idle unloader, choke function and vacuum circuit per the service manual.

[2oodoor]

Having a bit of trouble figuring this one out. Got an 89 accord lx. It diesels when shutting her down, and sometime sputters when idling at operating temp. Idles at 1200-1600 or at 800-1000. How would I know when I need to adjust the carb, or adjust timing. Discuss and share ideas fellas! :-)

These symptoms are a rather vague description of what has been discussed to smitherines for years here so me, not knowing any history on your car to this point, can only concour with what has been said, clean up the carb, check for broken vacuum lines, read up on a few systems of these carb controls and devices. From that point you can try a few things and come back with results and detailed description of what and when the problem arises...also check the coolant level.
The time to check all those other things is probably now right!