89 carb crazy idle.

[RamThis]

It just seems to idle different rpm's randomly. I attribute some of it to the fact that the car has 175,000 miles on it, and that the throttle shafts are probably worn, and they wont set in the exact same place every time you let off the gas, so sometimes it might idle at 1000 rpm, sometimes it might idle at 800 rpm, etc.

I still have to figure out exactly how to set that "Throttle Controller" thats mounted on the front passenger side of the carb with the throttle cable bracket. Right now its adjust back so it has nothing to do with idle. I have the idle set with the Throttle Stop screw up to about 1200 rpm out of gear with the AC off and no other electrics running. In gear, it will drop to about 800 RPM. Then when the AC kicks on, I have it set to keep the RPM about 800, its almost seamless transition. The PDF version of the shop manual talks about some weird stuff when setting the idle on this car, doesnt really give me a good step by step of what to do from what I can tell. Even mentions some crap about hooking up propane to a certain vacuum line and running a "propane enrichment" procedure to determine idle speed and mixture settings. WTF is that all about???? LMAO!!!! Ive never seen such a Cluster in my life. I'll get it figured out eventually I guess, unless you or someone can give me a better explaination of how to set the idle settings from scratch lol.

[lackej1971]

I am in the same boat you are in. Actually it sounds as though your idle is better than mine! Mine is more erratic than that. I think that as long as it is running dependably and not shutting off, then I would leave it alone.

I have accepted the fact that my idle will never be dead staedy as this car is old and carbed. So many mechanical, electrical and vaccuum operated things working in unison. It really is alot to ask of an older car. If you get this figured out, I would appreciate it if you would let me know what did it.

Thanks, James

[A20A1]

I still have to figure out exactly how to set that "Throttle Controller" thats mounted on the front passenger side of the carb with the throttle cable bracket. Right now its adjust back so it has nothing to do with idle. I have the idle set with the Throttle Stop screw up to about 1200 rpm out of gear with the AC off and no other electrics running. In gear, it will drop to about 800 RPM. Then when the AC kicks on, I have it set to keep the RPM about 800, its almost seamless transition.

Look for my post...
https://www.3geez.com/showthread.php?t=44074
I explain my proceedure for idle adjustment, some other members have used it and it helped.

[RamThis]

Look for my post...
https://www.3geez.com/showthread.php?t=44074
I explain my proceedure for idle adjustment, some other members have used it and it helped.

Well hell, My idle is already set according to your post LOL. Ive jacked with it and jacked with it thinking something was wrong because it would idle around 1100-1200 RPM in P or N, and drop down to about 800-900 in gear. I assumed there was a way to get the car to idle down to 800 or so in P or N, and there to be a solenoid similar to the AC boost that steadied the RPM in gear to keep it from dropping from that non loaded idle speed. Guess I had this thing set perfectly and didnt know it. I can rest better now LOL.

Im just used to computer controlled engines that dont do this wild fluctuation between in gear and out of gear rpm's. Guess Im expecting too much out of this car.....

[A20A1]

It's supposed to drop in gear... it's supposed to drop close to the throttle stop setting. The throttle controller if set right, will bring the idle back up some, close to what it was when the car was in park/neutral. So there is a little delay in the idle adjusting itself. But you should be able to get a stable idle... but not one that is constantly at 1200. You don't want it that high in gear anyways.

[RamThis]

Yeah I know that, I just thought I could idle it down unloaded (out of gear) to about 800-900 rpm, and put it in gear and it have a solenoid that kept the idle up to 800-900 in gear. I didnt know that these cars actually have to idle that high out of gear. Im used to my big v-8 idling at 700 no matter what in my Dodge Trucks, and my Acura idles at about 750 as well, no matter what is on or off. Just the difference in technologies, vacuum controlled VS OBDII PCM controlled....

[lackej1971]

Well, after reading you guys posts, I think that my idle could definitely be better. My car seems to want to die on me or run like crap until it gets warmed up. Is this something that the procedure you detailed will fix? I'll try it if it will.

Thanks, James

[VTEC_Inside]

Well, after reading you guys posts, I think that my idle could definitely be better. My car seems to want to die on me or run like crap until it gets warmed up. Is this something that the procedure you detailed will fix? I'll try it if it will.
Thanks, James

That sounds almost exactly the same as the problem I was having... It was the choke puller not functioning properly. As the car warms up the bimetallic spring opens the choke all the way (supposed to anyway), which is why its fine after a couple minutes of warm up.

[A20A1]

The choke puller might be leaking or the "O-RING" that is between the choke puller body and the carb body is leaking. The o-ring is at the front of the carb next to the screw that holds the choke puller body to the carb.

#18 carries vacuum
#26 connects to a solenoid in the black box, I'm pretty sure it bleeds off vacuum to limit how far the choke puller opens the choke.
It may or may not have an effect on the fast idle unloader, that would depend on if it has acces to it via vacuum line #18.

Anyways those are some things to check
Vacuum leaks from; O-rings, defective solenoids, vacuum lines, and diaphragms.
Coolant flow and coolant level is important for all the sensors that use it.
Thermovalves are part of the fast idle unloader and other cold start functions.
It's important the thermovalves are geting coolant and that they hold vacuum when they are supposed to and bleed vacuum when they are supposed to.

[Cant Stop]

hey old v-8'sfrom the 60's and 70's are just as tempermental
may not sound cool but runs fine is not a problem.

[RamThis]

hey old v-8'sfrom the 60's and 70's are just as tempermental
may not sound cool but runs fine is not a problem.

Man do I know that one LOL. Basically im comparing my two Magnum V-8's in my newer Rams in terms of idle. They are both rock steady no matter what load you put on them. Im just used to that basically, never knew a car had to idle over 1k rpm in N and drop to 800 in gear, always just assumed they had a way to stabilize the idle between load and unloaded. This is really the first vacuum controlled engine like this to ever mess with, so Im in new territory.

Sad thing is, not even my 68 Chevy Stepside or my 68 Charger R/T are this difficult to deal with. Fairly straightforward. I think these Hondas were a learning experience for the carbuilder in making a car whos emissions were as low as possible at the time without using a computer to do it. Just a bad era of vehicle design IMHO.

[A20A1]

Well they did it because they needed to meet the new emissions standards... but it was a part of the transition from carb to all EFI equipt cars. Something like that.

[Cant Stop]

absolutely right .
i live in a state where emissions are not monitored so i am opting to the straight up no black box just straight up carb technique.
i figure since its not inspected it will be easier to play with and fix with out the noodle box!
by the way a20a1 i dont seem to be subscribed to the thread where i asked about the manual secondary tab , do you know if i need to make this by hand or is it available to buy?

[A20A1]

it's off the A/C idle boost linkage

[Cant Stop]

thanks
um will this affect my a/c?that is the one thing i cant live without,however my car has been idling low and rough with a/c on latel anyways.

[lackej1971]

Ya Know, I really don't seem to see what the deal is with removing emissions equipment from these cars. What is the point? Personally, i depend on my car to get me from A to B dependably, and the last thing I am going to try NOW is mess with removing stuff from the carb. Maybe I'm being a pansy ass, but I don't own a race car and I never will.

So, Why do we remove this stuff? Thats a real question. What is the REAL advantage? My car FINALLY got to where it runs good and I'll be damned if I'm messing with it.

Thanks, James

[Cant Stop]

well lackej to naswer your question why mess with it?
i decided to strip it out because i had to pull the intake off due to a rotted freeze plug on the intake- i will post pictures tomorrow to show proof.- the rusty water in the radiator had ate it away.
so all that vacuum had to be removed because of the problem and it seemed easier to leave it all off anyways, asa a lot of the hose had vulcanized
and broke off. i have also decided to remove the line going from the oil water seperator off the intake since all that nasty oil vapor has really coated my in takes up badly, after cleaning the junk out it should run better in order to remove the oil/water seperator i bought a edelbrock air breather and slipped some vynl tubing to it and the top of the seperator it just clears the intake.
well i am going to make or add to a different thread all this work and i will keep you posted.

[RamThis]

I guess I did mine the hard way, I put it all back together like it came apart when I fixed my freeze plug problem. All three plugs were rusted through.

BTW, Rusty water doesnt corrode the freeze plugs, running straight water in there is what usually does it. The freeze plugs are made of steel, while the intake is made of aluminum. The water acts as a conductor, and the two metals mixed with the water and any chemicals in the water work to oxidize the steel freeze plugs and corrode them away. Thats where you get the rust from.

I took the intake off, and my neighbor has a commercial type Heli-arc machine that we just bridged over the freeze plug holes solid, and viola, no more leaks, ever.

Also, just some food for thought, freeze plugs are not for "freezing", or, shall I say, to save your engine should it freeze solid. They are really just holes to dump out the sand from the casting process. All these blocks and intakes and such are lost sand casted, then machined to get all your proper mating surfaces. It just became a mechanic's term to say to unwitting owners that if the car freezes from not having enough anti-freeze, that these plugs are supposed to magically pop out and the water will expand out the hole or some crap like that LOL. Water doesnt work that way. You may come out to find all your freeze plugs laying under the car, but, your block or your heads may be laying in two or three pieces because there are so many small passages for the water to get in, it will most likely break something, and its sure not going to just squeeze out that hole LOL.

[lackej1971]

That is a very interesting reason for removing all of the stuff that you have removed. Now I am a bit worried, because before I flushed my radiator out TWICE to get most of the rusty water out, it was really BAD looking. When you said that your hoses were rotted, which ones were they? It just makes me wonder if mine has some bad hoses or something because of the crappy coolant that was in it.

Now, since I replaced the starter and did the flush out and replaced it with GOOD A/F, my car has progressivly ran better. Most of the time now, I don't even have to pump the gas to make it start. That is a BIG IMPROVEMENT for me.

Thanks, James

[Cant Stop]

the hoses under the intakes went bad and a freeze plug(even though it doesnt save anything if it freezes)went bad. i took pictures sorry i cant paste them here yet but look for them with a search here: home.earthlink.net/~andyk65
this is my personal web page i will add some more pic's soon

[pathfin9]

Noob here. My idle is at about 2200 rpm when I start it cold, but if i tap the gas a little it settle back down, and if i let it sit it will go back to 2200rpm again. However, when I drive, its normal.

-John