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Good day, dudes and lady dudes!

I hail from the sunny bottom of California and have an all stock 1984 1.5 Honda Civic sedan.

I can't seem to get my idle under 1000ish RPMs. I've adjusted all the screws, and still can't seem to get it under 1K. It's a remanned carb from National Carburetors, and I'm trying to get my baby rolling and registered, but can't do anything till the idle is at 700 +/-50RPMs like it should be.

Helpful tidbits:
Rebuilt engine
New starter
New ignition coil
New plugs, rotor, cap, and wires
New fuel filter
Good compression check
Good spark

Help Honda lovers. You're my only hope.

 
Rep Power: 222

checked vacuum lines? i'm not too familiar with carbed civics unfortunately

 
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Thanks for the reply, Colin!

I totally forgot to mention, that, to the best of my ability (and until I went cross-eyed) I validated that my eleventeen thousand vacuum hoses were all going in at least the right direction to their final destination.

While the vacuum layout for my 84 isn't pretty, I'm pretty sure I have it more or less in the correct order.

 
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Ok, so, while fiddling with the A/F Mixture screw trying to get my idle down, I now have black sooty exhaust.

I got my hands on the 84 Civic Service Manual, so at least I have that going for me now.

 
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Update:

I was able to do away with my black sooty exhaust. I still can't get my idle under 1000, but will hopefully get it under control tomorrow. Will post all results as I go.

 
Rep Power: 367

Is the butterfly closing fully?

 
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Butterfly? I believe it is.

And, I've adjusted ALL the screws I can as far as I can to get the idle as low at 1250, but still can't get it any lower. I'm pretty sure I've also closed the A/F Mixture Screw as much as I can and still no drop under 1000 RPMs.

Maybe a bad O2 sensor, among other things? Pretty sure everything on this car is still from 1984 if I haven't changed it.

I still occasionally get some bad smelling exhaust.

 
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Think I might've found the problem.

A few of the vacuum lines were off.

26, 31, and 12, which are Control Switch B (26), Vacuum Switch B (31), and the Primary Slow Mixture Cutoff Solenoid (12).

2 of the 3, 31 and 12, seem to be at least a little important to what I'm trying to do and might be part, if not all, of my problem.

STAY TUNED!

(Updates as soon as I jump back on it in the morning, Hondanians!)

 
Rep Power: 367

Check also the nozzles, if the idle one is not too big.

 
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The nozzles all seem fine, sdaidoji, unless you have a pic of what a normal one should look like vice one that's too big.

I have, however, come upon a strange finding.

When I tinker with the car after the evening has cooled down, all my indications seem to be better/normal.

But in the day, when it's warm, is when I get the high idle that won't go below 1500 RPMs.

Anyone sciencey enough to help me with this?

O2 sensor, right?

 
Rep Power: 367

worth a try?

so, when the air is more rarefied (warmer) it have issues, but when colder, it works fine?

(never worked on O2 sensor and carbs... Only carbs on older dizzies and some electronic ignitions...)

Hey, have you checked the timing?

 
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I'll check the timing again, after I change out the O2 sensor. I checked the timing when I got it back up and running.

And yeah, that's the case, if I go out right now and let it warm up, it'll act like everything is ok and idle like it should.

And during the day, when it's warm, it'll get up to 1500+ RPMs, no matter how much I tweak it and mess with the carb screws.

I can't seem to get my idle float to be consistent during the day, either.

 
Rep Power: 367

vacuum tubes somewhat getting bigger when warmed up?

 
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Nothing noticeable...

 
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Soooooo,

The O2 sensor was horrific. Upon changing it, I had to tweak everything on the carb back to where it was before. After that, it idled like a beauty at 750 +/-50 RPMs.

But NOW, it seems to bog out and die trying to go uphill.

What's The Frequency, Kenneth.

 
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up the mixture a little?

 
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good to hear it idles

I don't know the details, but is the carb two stage?

 
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So, sdaidoji, I can't say I know that one way or the other.


And Colin, I did, just enough to get it to idle and well below the rich, gross black smoke threshold.

I can get it to turn on, I can get it to idle at 750ish RPMs, and I think I have the mixture right...I just have to wait for it to get cold again to see whether or not I'm right.

This has been a very long exercise in determination at which, various times, I've just wanted to give up.

...jajaja...good thing I'm more determined than not.

 
Rep Power: 222

Yeah that is the downside to carbs, alot more finicky and need to tweak once in a while. Hopefully you've got it all sorted out now

 
Rep Power: 367

if it have 2 stages, you wull see two holes in the throttle body, with two different butterflies.

depending on the carb, it could have either vacuum or mechanical activation for the 2nd stage (if your have it)
if the activation is not good, or opening too much, it could bog down

 
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Oh, then yeah...jajaja...I immediately knew what you meant. And yup, my second stage is vacuum operated.

I think, more than not, that it's just that the carb isn't tuned properly as it should be after I kept messing with it BEFORE I replaced the O2 sensor...just gotta be patient and keep working.

 
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Ok

Buen suerte!

 
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Gracias amigo!

Here's to hoping she's a good girl and works with me!

Because MANNNNNN has she been difficult up until now...jajaja

 
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My Valentine's Day woe, my good fellows (and ladies if there's any)...

I love her, but she doesn't love me, sadly...

Now, all she does is crank and not start.

I'm really trying to NOT lose hope...but MAN is she not making it easy.

 
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Ok, so I'm going to home and say that it's the fuel pump. Yes, I know I have a mechanical fuel pump. But at this point, what else could it be? I know I have spark and my timing seems fine. On the carburetor side of my fuel pump it's dry, so I'm going to home that the 30$ I spent on the fuel pump will be nearing the end of the money I have to spend to get her going again.

She DID more or less just sit for like 3 or 4 years...so it should totally be the fuel pump...right?

I mean, effballs, I've already JUST replaced about everything else I could up until now...jajaja

 
Rep Power: 222

It sat for 3 or 4 years? Yeah that could cause issues with the fuel pump. There should be a way to test it to make sure