Idle problem (irregular) on my hatch.

[2oodoor]

I too
Have the swooshness

[carotman]

Well, I replaced the whole intake manifold/carb/Vacuum box assembly from another 3g that I knew was running right. The problem is STILL there!!!! I can't beleive it.

I also replaced the distributor because mine was full of oil. Also replaced the coil. I checked the compression and it was at 170 everywhere....

I really don't know what to check now. I can hear a rattle comming from the cat converter, could it be choking the engine at lower rpms?

When I spray carb cleaner in the barrel, it picks up on speed and idles runs better. Same thing if I partially close the choke plate. It likes the extra venturi effect.

Anyone has an idea?

[2oodoor]

wow, that one is a ghost
Yes definately if you hear any rattling in the converter, 99 percent of the time on any car you will have a restriction.
I do not know how that would make your car run better when you richen it up though, hmmmm
Did you check the screen pickup inside the tank like synikil suggested?
Have you adjusted the valve lash?
You replaced the dizzy and you mean to say you showed zero improvements in the way the car behaves? That would entail rechecking the timing and vacuum advance connection I shall assume. geez all of those changes should have given you some sort of improvments
recheck the pvc plumbing, it is separate from the items you replaced. That plastic piece that holds the actual valve usually deserves some study, they warp, crack, split, and the valve does not fit tight sometimes as well.

[A20A1]

Also, I noticed that when the screen is replaced that the swoosh sound that you hear when you unscrew the gas cap is alot less intense than before. I think that if you here a big swoosh that it's because the fuel pump is pumping more pressure than normally required. So maybe to much swoosh could be a indicator of a clogged fuel pump screen.

Interesting correlation, I used to have intense vaccum cleaner like swooshes when I opened my tank.

[A20A1]

I can hear a rattle comming from the cat converter, could it be choking the engine at lower rpms?

nah, because if it was choking low rpms it would be even more noticeable at higher rpms, unless there was some unknown added cleaning of the cat with increased heat or something.

So you're still running lean?

Maybe it's the ethanol mix taking effect.

But you don't have a vacuum leak and your fuel system is okay?
so that means the carb needs tuning or some vacuum operated device is bleeding off vacuum like a busted brake booster or solenoid or something.

Have you tried running the carb with nothing attatched to the intake manifold or carb?

No brake booster, no vacuum to the distributor, nothing to the carburetor except perhaps #14 to the powervalve, and not even any vacuum hooked to the idle diaphragms.

Use the black throttle stop screw as the only means of idle. make sure the it relatively warm, or decent weather and the car is fully warm.

Then see if the problem is gone, if not at least you can norrow it down to something electrical or mechanical... or if the problem goes away you can reconnect the disconnected parts till the problem comes back.

[2oodoor]

ahhh, brake booster... the other thing not attached to the intake manifold.
I noticed on my LX that applying the brake in the morning when the engine is cold, backing out of the driveway, significantly changes the mixture. Once warmed up a little the change is not noticable .

[carotman]

Well, I guess I'll try to remove every single vacuum line on the carb itself and see if I have any kind of improvement.

I got a spare fuel pump I'm going to try also. The valve lash has been adjusted last fall when I did the timing belt (like 6k miles or so). I'll re-check that again just to make sure. Any solution is a viable solution now.

[A20A1]

ahhh, brake booster... the other thing not attached to the intake manifold.
I noticed on my LX that applying the brake in the morning when the engine is cold, backing out of the driveway, significantly changes the mixture. Once warmed up a little the change is not noticable .

You don't have your brake booster connected to the manifold?

[2oodoor]

You don't have your brake booster connected to the manifold?

I caught that right after I hit the post thread button lol, of course it is 'attached' I meant to say not a part of the intake mani assembly as one would have in replacing the assembly like he did.

[carotman]

I "kinda" found the problem. Or at least I know where to look at now.

I noticed that the slow mixture solenoid only gets 2V or less. That's not enough for it to click.

There's only 2V comming directly from the control unit itself. When I connected a 12V wire to the solenoid, my idle jumped sky high (2500 rpm) and I was able to stabilize it at 750 rpm by turning the throttle stop screw... the thing purrs now.

I really don't know what could be causing this except a faulty Control Unit under the driver seat. I tested the following like the manual says:

- Voltage between connector (1) an (10) => OK
- Ground continuity with wire (10) => OK
- Voltage between (7) and (10) => Somewhat OK (10V since it's a pulse comming from the coil)
- Continuity between (13) and (10) when shift lever in (N) => OK (80 ohms)
- Inspect vacuum switch A and B => OK (12V at idle, no voltage as rpm and vacuum raises)
- Inspect Speed Sensor => No need
- Inspect Thermoswitch => OK (No voltage above 60 C)

Any ideas before I try to find a replacement unit?

I thought about connecting it to a constant 12V but the manual says there should be no voltage if decelering at a speed above 24 km/h

[russiankid]

I "kinda" found the problem. Or at least I know where to look at now.
I noticed that the slow mixture solenoid only gets 2V or less. That's not enough for it to click.
There only 2V comming directly from the control unit. When I connected a 12V wire to the solenoid, my idle jumped sky high (2500 rpm) and I was able to stabilize it at 750 rpm... the thing purrs now.
I really don't know what could be causing this except a faulty Control Unit under the driver seat. I tested everything mentionned in the manual and still only get 2V.
Any ideas before I try to find a replacement unit?

Is anything spliced into that wire? If not just replace the unit and got from there.

[Ichiban]

I'd just hook it straight to the ACC power. All I think it does is cut the idle mixture circuit when decelerating.

[A20A1]

I'm guessing the extra vacuum on decel would pull out too much fuel if it wasn't shut off.

[carotman]

Yeah that's what I think too.

I'll try with a different control unit and see if it solves the problem.

[steveko]

Hey,carotman keep us posted on what you come up with after the fix. Because, my car has the same exact symptoms. And it sounds like we've done alotta the same repairs.

steveko,1988 Lx accord 5sp.

[2oodoor]

I would look back in the manual and find the carb control vacuum with electrical diagrams for your engine. The ecu 'knows' when you are decelerating , that would have to be done via vac switching electrical. Somehow when you did vac removal something was crossed maybe? I thought some of the purpose of vac removal was to take the ecu out of the picture.
another way to skin a cat>>>
I wonder if you could use a dashpot on one of the throttle controlers, in place of it, that would not let the throttle snap shut when you let off the gas, but let it slowly set the thorttle down after you let your foot off.
I think those type solenoids sometimes in other makes, are energized with ign constant, so either way you could leave it in place if you accomplish the (tapering) of mix on decel.
random thoughts I guess https://www.3geez.com/forum/showthread.php?t=59764
a couple of vacuum reading electrical swiithes in the diagram in this thread, any report to the ecu?

[A20A1]

After all that, I forgot he did the vacuum removal.

[carotman]

Well, Since it didn't change anything, I reinstalled the vacuums the way they were from the factory.

If someone actually removed the blackbox from the carb, the solenoid would be constantly activated by the "ECU" since it would not see high vacuum from switch A or B. Maybe it still deactivates the solenoid from the VSS signal. Still people with a broken speedo would experience weird behaviors.

Any thought on this?

[2oodoor]

. Still people with a broken speedo would experience weird behaviors.

Any thought on this?

yeah, well since I don't wear those, I can't really say but I completley agree all the elements are there.

[steveko]

According to the manual it says to check the voltage at the solenoid connector. This should be with the car not running and key on. You should have 12v respectively.

[carotman]

Well, I wired it up to the ACC power and no problem so far.

The car did idle a bit high after driving for a while tough. Could be related to this or not. I'll have to find out. I'll replace the control unit soon anyway.

My alternator died so I need to fix this 1st... damn old cars hehe.

[steveko]

Man it sounds like your dumping alot of money in too this car all at once.I have replaced my alternator also, along with the battery.Also the control unit isn't a cheap ordeal. Have fun putting that alt in. I did. Joking of course. While I was there I put in a new water pump also due too a tiny weep.

[Kelvin]

My car idles like crap also. At idle, it sounds like a diesel, almost like not all the plugs are firing, but it gets over 30mpg and drives fine around town and on the highway, it's just idle.... so... I dunno what the hell is going on.

[carotman]

Man it sounds like your dumping alot of money in too this car all at once.I have replaced my alternator also, along with the battery.Also the control unit isn't a cheap ordeal. Have fun putting that alt in. I did. Joking of course. While I was there I put in a new water pump also due too a tiny weep.

Well, In fact I didn't spend much. I got real good deal on parts. The "new" intake manifold/carb assembly was like 30 bucks. The alternator is like 10, I'm only replacing the brushes. The rest seems to be in good condition.

Oh, and you're right that alt is a bitch to get to. I managed to route it through the heater lines. All I needed to do is remove the speedo cable and the bracket holding the heater switch.