primary slow mixture cut-off solenoid valve 1989 honda accord manual, carb,

[cat]

My accord has this problem that it won't idle. Start up is fine, runs at 2500 rpm, but then after warm up it will not idle. If i give it throttle it will run but as soon
as i come to a stop, it will die if i don't continuosly give it throttle. I've read where the primary slow mixture solenoid valve located on the back of the carb will
shut the car down by blocking the idle circuit via a plunger. I disconnected it and tested it by turning ignition key to start, and the plunger did not retract. I tried
to access the switch but could not test further b/c could not open the connector. My question is for anyone who knows, is this cutoff solenoid absolutely necessary?
What is i just fill the port where it connects with silicone--- or some other material??? What are the possible complications aside from the engine running on a bit
on shut down--- thankks for any information on this

[POS carb]

It is purely to stop fuel in the idle circuit and it's going to run on if you somehow disable it. All it needs is a 12v run signal to operate so if it isn't getting voltage there is a blown fuse or broken connector.

Get another one from the junkyard.

Don't put silicone in it, if it gets sucked in you have a whole new problem that'll probably end up costing you a new carb. You might be able to remove the plunger and use the defective valve to keep it sealed if you insist, but you are going to have to turn back the idle boost screw on the passenger side. One good backfire and you'll be searching the vacuum birdnest for the hose that blew off.

[2oodoor]

Good info

You still haven't tested the circuit correct? I would have to trace that on a wiring diagram and make sure there isnt a controller/ sensor upstream in the circuit that controls voltage to that solenoid before I could say the part is bad. You can still test the solenoid with tst leads from a 12v source but you need to get it unplugged

[cat]

Thanks to POS carb and 2oodoor for your responses. Update: i tested the primary slow mix cut off solenoid with a jumper from the battery, and it works, the plunger retracts
as it should, next i was able to get to the connector under the carb (buried under scores of vacuum lines), and I tested the engine side, and it has battery voltage, so i think
this solenoid is not the problem for my idling issue. The car starts fine, runs a little fast 2500 to 3000 rpm, and then slowly comes down in rpm until finally if will just shut
off if i dont give it throttle. I then have to keep the rpm up around 2000 for it to run. If i let off the gas the rpm plummet quickly to shut down, so in essence it will not hold
an idle. To make it even more complicated, sometimes it will idle just fine, but of late it seems to be more down then running. When it gets into its funky mode, it sounds like
it's missing badly. Luckily i have another car, so I can work on the Accord in a relaxed way. I've thought about fuel starvation, i plan on checking the fuel pressure, and removing
the fuel line at the carb to see the volume of fuel in 10 to 15 sec. Any advice would be much appreciated. Plugs, wires, coil are relatively new. I removed the plugs and they
looked ok. The only other thing i've found is a hose that connects to nothing that originates in what think is the brake booster ( it's in the left front next to the power steering
resevoir) Any way, any thoughts are welcome

[cat]

update: On further investigation by reading through numerous past posts, including one by member "dj99" I figured out that
the problem was with the primary slow mix solenoid valve, specifically that it had lost it's ground. According to aforementioned
member's post (in 2004), he solved his Honda no idle problem by merely sanding the area of the carb where this solenoid valve
connects, thus restoring the ground which now allowed the plunger within the solenoid to retract when he turned the key to the
on position. So I did the same and viola, my car was happily idling at approximately 950 rpm. It had been idling fine for about
one week when yesterday the problem returned, what I think is happening now is that the solenoid is probably malfunctiong on
an intermittent basis (the car is 27 yrs old). I probably need a new one--- anyone out there know where I can get one??? Any
information would be appreciated.