high idle , and its getting worse

[typhoon]

Hi,

I'm new here, and have a problem with a '89 2bbl accord.

The idle was high around 2K and today it just got worse, up to 3K and its getting scary.

I spent several hours the other day trying to figure out where the problem could be, and I think it might be the fast idle valve.

I was reading some pages out of a manual, and I thought the test was to remove both vac lines to the fast idle valve. Then apply vacuum to the vac port toward the front of the car, the idle should drop. If it doesn't, then it says to inspect the fast idle valve for damage, leaks, etc.

ANYWAY.... I think I found a replacement for it at a local autozone, they called it a idle control valve. Something like $14 or so.

Problem is I have no idea how I'd get that valve off to replace it. It looks like theres two screws holding it on, but there are hard vac lines running right behind it that won't allow any room for removal.


Please help me out here, as I don't want to drive the car in its current state, and taking it to the dealer is not what I'd prefer to do.

thanks
Scott

[typhoon]

I know this is a topic that comes up quite often, and just want to explain that I have searched through many topics, but haven't found any instructions on an R&R of the fast idle valve.

In the following page, in the first pic, vac ports A and B are the ones I was trying to test.
http://87accord.com/carbpage.html

Anyway I did notice that if I stuck my finger just above the throttle linkage I could lift up on something in there and it would click and release the throttle linkage so that it would release the tension and allow the throttle linkage to sit agianst the throttle stop screw. Anyway whatever it is that I can click manually, is what I believe is causing the problem. Not sure if that is what the fast idle valve's job is, but it would make sense.

Once I manually would click that to release, the idle would be good, when the car was started, as long as the gas pedal was not pumped prior to starting.

If anyone can tell me if this sounds like I need to replace the fast idle valve, and any steps that it would take to get that thing out of there, as the vacuum lines run directly over it and seem to block access to the screws.


thanks
Scott

[rustyaccord]

had the same problem. Turned out that I basically needed to lube+adjust the throttle cable. I could actually put my foot under the gas pedal and reduce the rpms. Also I think you can just shut of the fast idle but adjusting it all the way down (I don't know if it goes that far). I never use it, just knock it down as soon as I start the car.. *shrug*

[A20A1]

first Check your coolant level...

It may also be a vacuum leak to the fast idle unloader that is causing the problem. There are a few thermo-valves on the intake manifold that can go bad... but not enough coolant can cease their operation... also just run over the vacuum lines and check for cracks or really stiff and brittle hoses.

The thermovalves are on the drivers side of the intake manifold, along the rear.

As for removing that peice by itself... I'm not too sure... it may require unbolting the entire carb or the hard lines surrounding it.

[A20A1]

Oh and be very careflu if you decide to pull vacuum lines off a thermovalve cause the plastic ports coming off the valve snap easily.

[typhoon]

Originally posted by rustyaccord
had the same problem. Turned out that I basically needed to lube+adjust the throttle cable. I could actually put my foot under the gas pedal and reduce the rpms. Also I think you can just shut of the fast idle but adjusting it all the way down (I don't know if it goes that far). I never use it, just knock it down as soon as I start the car.. *shrug*

How did you lube the cable? Did you have to remove it? Mine does look rusty, and it could be the problem. As a matter of fact, yesterday I hit the throttle hard, kinda out of aggrevation, RPMS went up to about 4K, as I was trying to see if it would bring it down.... thats when it started to idle really high 3K range. So maybe it is the cable getting jammed up. How long does it take to lube the cable, and where at on the cable?

As far as not using the fast idle, how did you eliminate the use of it. It seemed that when I removed both vac lines to the ports the idle would be fast, so is there a way to bypass it? It won't work when I try to "knock down" the idle with the pedal.

[typhoon]

Originally posted by A20A1
first Check your coolant level...

It may also be a vacuum leak to the fast idle unloader that is causing the problem. There are a few thermo-valves on the intake manifold that can go bad... but not enough coolant can cease their operation... also just run over the vacuum lines and check for cracks or really stiff and brittle hoses.

The thermovalves are on the drivers side of the intake manifold, along the rear.

As for removing that peice by itself... I'm not too sure... it may require unbolting the entire carb or the hard lines surrounding it.

I will check the coolant as I haven't done so yet. :(

I didn't seem to feel good vacuum to the fast idle unloader, so I t'd off a vac line that runs to the canister on the intake tube that opens the door for hot air return. That one seemed to have good vacuum.

As far as thermo-valves. Are those AKA coolant temp sensors?
If so, how many are there? I wouldn't mind changing them just to know they are good. I'm new to carb's, so bear with me.
How do the thermovalves interact in a carb setup?

Thanks all for the help. Wish I didn't have to work today, and tomorrow, because I really need to fix this.

I really want to lube the throttle cable though, so if anyone can give some instruction on what to use, and what areas of the cable to lube. It seems that the cable is kinda rusty, then right on top of the valve cover the cable enters the plastic sheath, so I'm just wondering how the lube is able to get into that area under the plastic to ensure it gets lubed in there.

thanks
Scott

[rustyaccord]

Originally posted by typhoon
How did you lube the cable? Did you have to remove it? Mine does look rusty, and it could be the problem. As a matter of fact, yesterday I hit the throttle hard, kinda out of aggrevation, RPMS went up to about 4K, as I was trying to see if it would bring it down.... thats when it started to idle really high 3K range. So maybe it is the cable getting jammed up. How long does it take to lube the cable, and where at on the cable?

As far as not using the fast idle, how did you eliminate the use of it. It seemed that when I removed both vac lines to the ports the idle would be fast, so is there a way to bypass it? It won't work when I try to "knock down" the idle with the pedal.

Just take it off the carb and dump a few drops of oil on the wire and pump the accelerator, and add some grease to points under the dash. Manual says there should also be 4-10mm (!!) deflection when it's hooked up to the carb. Less than 30 minutes I'd say..

Well I didn't personally, but I see how you could when I adjusted it. It's the set screw near the throttle cable (one which people seem to mistake for the idle stop screw) just turn it out as far as possible or just remove it.

[typhoon]

Just take it off the carb and dump a few drops of oil on the wire and pump the accelerator, and add some grease to points under the dash. Manual says there should also be 4-10mm (!!) deflection when it's hooked up to the carb. Less than 30 minutes I'd say..

looking at ....http://87accord.com/carbpage.html
do you have to remove that nut shown as "D" in the first pic to take the cable off?
and when you say deflection, is that like slack at the throttle linkage?


Well I didn't personally, but I see how you could when I adjusted it. It's the set screw near the throttle cable (one which people seem to mistake for the idle stop screw) just turn it out as far as possible or just remove it.

is it the screw labeled "E" in that first pic?
if so, i noticed when I started the car, the tab that usually sits agianst that screw is off of it about a 1/4", with a high idle. Nothing I do, even trying to knock down the idle with the pedal will get it back to sit agianst that screw.
Only with the car off, and reaching under there and clicking something will it release the linkage and let it sit agianst that screw.

[rustyaccord]

No, you can just slide it out after you loosen the cable enough I believe, thought it might be easier (?).

Yes, that's it.. Look at the opposite side for the AC fast idle, which looks almost exactly the same. That may be way out of adjustment. Also make sure you lubed everything really well. I don't think there is any other control for idle....

[A20A1]

Thermo valves open and close vacuum passages...

the temp sensor on the intake manifold send the signal for the guage cluster only...

the Temp sensor on the radiator controlls the fan switch.

you have 3 thermovalves.

2 are on the rear of the intake manifold on the drivers side... and the is one more (controlls the secondary vacuum bleed) on the thermostat housing.

[typhoon]

Originally posted by rustyaccord
No, you can just slide it out after you loosen the cable enough I believe, thought it might be easier (?).

Yes, that's it.. Look at the opposite side for the AC fast idle, which looks almost exactly the same. That may be way out of adjustment. Also make sure you lubed everything really well. I don't think there is any other control for idle....

Ok, understood.

I saw the AC fast idle on the other side, I'll have to check that one as well.

What kind of oil do you recommend to use at the linkage, and what kind of grease at the firewall on the interior?

I got my fingers crossed that its just needing to be lubed, as getting to that fast idle valve to R&R looks like it might be a bit of work.

I'd much rather find a way to elimate its function if it turns out to be the problem. I just can't see how backing that screw out would be the way to do it. Because the further you back that screw out the lower it would idle if it would actually be able to be "knocked down" to that screw. Problem is, even trying to "knock" the idle with the pedal won't bring the linkage back down to that screw. The only thing that I found that works is, and this is not a solution, is to stick my finger right over top of the throttle linkage and lifting up on a tab that then releases the linkage down to that stop screw.

I'm thinking either the throttle cable is jammed up and isn't getting enough to "knock" down that idle, and/or the fast idle valve is shot so it cannot bring the idle down either.

[rustyaccord]

Just a few drops of 10w30 and generic grease worked for me. I didn't really pay that much attention to it - just generic lube points. The only thing is you really want is some lubricant to "flow" down the throttle cable. All those years of lying across the valve cover and over the exhaust manifold probably accelerate corrosion inside...

[typhoon]

Originally posted by A20A1
Thermo valves open and close vacuum passages...

the temp sensor on the intake manifold send the signal for the guage cluster only...

the Temp sensor on the radiator controlls the fan switch.

you have 3 thermovalves.

2 are on the rear of the intake manifold on the drivers side... and the is one more (controlls the secondary vacuum bleed) on the thermostat housing.


I was following the procedure on this page... http://www.chitownsyty.com/albums/albuo74/aca.jpg
and didn't have a vacuum pump, so I borrowed another vac line with good vacuum on it, and put it on the port shown on that page. It says the fast idle should drop, well it didn't. So thats where I'm at.

It says to inspect the diaphram of the fast idle valve, but I don't see any easy way of getting the cover off it.

Also says to remove the choke cover, which I assume means that you have to drill out the rivets??

Thanks for all the help.

[A20A1]

yup you gotta drill out the rivets.

[typhoon]

Lubed the throttle cable up this morning with some white lithium grease, and it seemed to do the trick. :D :super:

Actually did the trick so well that I gotta go back in and raise the idle a bit, because its stalling now when I come to a stop. :lol

The cable looks to be in bad shape, so it might have to be replaced soon. Right where it passes over the valve cover the plastic shealth is falling apart.




Couldn't hurt to replace the vac lines, and while I'm in there try and find the thermovalves and make sure they work.
Has anyone redid their vac lines, with silicone hose? And if so, did you buy the hose in a kit?

[MrBen]

Where is the cable. I'm not too good with carbs. I take off the air filter crap and now what? Where do I look? How does it come off, and do I need to to lube it?

[brennan.o]

That happened on my 89 lxi last week...all i did was put some grease on the throttle cable and spring area, it fixed the problem