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locknload68
07-28-2002, 07:36 AM
What vacuum lines do I need to remove to disable the fast idle?

Reason being that I used to always be able to tap the gas and it would turn off, it no longer does that...fast idle stays on til the car has warmed up and it's 80-90 degrees here.

Thanks

dj99
07-28-2002, 08:04 AM
(According to the manual...)

Fast idle CAM (choke?) is engaged via the accelerator pedal. The fast idle unloader on the carb has two diaphragms controlled by thermovalve A in two steps. When the coolant temp is reaches 59F is stage 1 (fast idle), up til 131F is stage 2 (fast idle first step) and over 131F is stage 3 (fast idle off).

So to answer your question, there is no hose to turn it on. :)

If you are interested in troubleshooting the fast idle unloader system (looks fairly simple), I would be happy to send you the page from the manual. Send me an email.

locknload68
07-28-2002, 01:47 PM
I've got a manual. It just doesn't say that if I remove the vacuum lines from the unloader that it will disable the fast idle. I just want to make sure that if I pull those two lines off, it won't make my car redline or anything (happened once when I removed one).

POS carb
07-30-2002, 06:34 PM
Originally posted by locknload68
Reason being that I used to always be able to tap the gas and it would turn off, it no longer does that...fast idle stays on til the car has warmed up and it's 80-90 degrees here.

Thanks


that's how it's supposed to work, so your vacuum system actually fixes itself, mine only seems to lose parts :lol

locknload68
07-30-2002, 07:39 PM
But I don't want the fast idle at all. lol It's just really annoying when I can go down the road without my foot on the gas at 40 MPH. I used to be able to tap the gas and it would turn off, but now it doesn't.

So, will plugging those vacuum lines on the unloader disable it?

doug
07-31-2002, 03:57 AM
no, plugging the lines will give you what you already have, no unloading. check the thermovalve and all lines to it, maybe one of the plastic prongs off the valve has broken and the unloader circuit is no longer working. the thermovalve A, the one you need to work on is almost directly under the a/c idle boost dashpot on the drivers side of the carb, it screws into the intake manifold.
my guess is it's got a broken prong or just stopped working because it is the reason (most likely) that the fast idle does not unload. basically either the thermovalve is no good or you have a leak in vacuum circuit #17, #18, or #19

locknload68
07-31-2002, 06:09 AM
Thanks Doug, that's exactly what I wanted to know :)

POS carb
07-31-2002, 10:27 AM
just connect the unloader to constant vacuum, it's let you have fast idle when you start and will shut off the instant you hit the gas.

locknload68
07-31-2002, 06:29 PM
Where is a place I can tap into for constant vacuum?

doug
08-01-2002, 03:10 AM
if you want to do the constant thing, you can put a T connector on the 2 lines, #18 & #19 out of the carb dashpot module and connect to #17 vacuum line that goes into thermosensor A,
#17 is the line on the ouside top. (there are 3 lines on thermosensor A #19 top inside, #17 top outside, #18 bottom)
or you can do the T connector at the thermosensor.

joebeets
08-01-2002, 09:51 AM
Originally posted by locknload68
Where is a place I can tap into for constant vacuum?

It may not be your "fast idle system" causing the problem if you have automatic. It could be your throttle controller not retracting as it should. (See post below.)

Anyway, the electric choke is also somehow involved, so retracting the unloader may not solve your problem if the choke is still preventing kickdown.


My newsgroup post:

>My 88 Accord DX...(has)...has a very fast idle (almost 3K) that >won't come down
>normally, often lasting thru the first half hour of driving, even on
a
>warm day. I've already tested the fast idle unloader and swapped the
>ECU.

Turns out, it was the throttle controller. Apparently it has a triple
purpose. In addition to its normal ones, keeping the throttle from
slamming shut, and regulating idle, it also extends, after the engine is turned off and vacuum is removed, to hold the throttle open for the next start, so the car can be warm-started without pushing the gas pedal down.

In my case, it stayed in the extended position. Eventually it got regulated
vacuum from frequency solenoid valve C, but until then it kept my idle
way too high.

My workaround for now is to disconnect the Throttle Controller (hose 20) from FSV C (right fender) and
route it instead to the test port (?) nearby, (a metal nipple with a
plastic cap) which supplies full vacuum when the engine is running,
thus retracting the TC fully when the engine is on while still
allowing it to extend normally on shutoff.

ACCORD EX
08-01-2002, 12:02 PM
what to do if the fast idle doesn't load auto ! ?? i need to tap gas after i turn the car on to load it ??/

MIKE

POS carb
08-02-2002, 03:50 PM
I HAVE MINE SET UP LIKE THAT POST BY 'MY 88 ACCORD DX'

Shagen
08-03-2002, 05:05 PM
Along the same lines my car sometimes wont go into fast Idle and then it will only run at like 750 RMP's or stall out. I found that if I pump the gas before starting it doesn't do it as often but why does my car stall when cold?

dj99
08-03-2002, 06:09 PM
I've pumped the gas pedal twice before starting the cold engine for the last 14 years. I think it was in the owner's manual, and it is what sets the choke and idle cams properly.

locknload68
08-10-2002, 01:06 PM
I need some more help. I hooked 17,18, & 19 up to a T-connector and the fast idle still stays on. I need some more ideas please.

doug
08-10-2002, 02:04 PM
check to see if 18 & 19 are opposite on the T and 17 is pulling both of them. otherwise it may be the throttle control diaphragm
is someway stuck, that's line #6, take a look at the right side of the carb here,
http://87accord.com/carbpage.html

locknload68
08-10-2002, 03:00 PM
Thanks. I think that my problem this time was my a/c boost screw. My screw was missing so my dad put in a new one and I think he screwed it in way to far.

So I was driving my car and it was idling at 2500 the WHOLE time and I couldn't do anything til I got home. But I turned the boost screw out so it's not touching and then messed with the #17 vacuum. When I left the #17 hose to the airbox unplugged, it would idle around 1250. Once I plugged the hose, I could see the fast idle unloader retract and the idle would go up. So I'm thinking that there is something wrong with the unloader. I'll have to take it off sometime and look at it but it looks like it might be hard to get off cuz of all the lines running behind it.

As for the throttle control diaphragm, I don't think it's the problem cuz the screw for it isn't even touching the throttle.

Thanks again.

doug
08-10-2002, 03:08 PM
keep us posted on what's up with it. you'll get it tight at some point. good luck.

motoboy
08-12-2002, 06:39 PM
:banghead:


I own an 89 Accord LX. I bought it from a lady who let it set in her yard for about 6 months. I had no car at the time so I decided to purchase it since it was only $800 and all she said it needed was a new alternator and the belt (which also ran the water pump). I got it home (after re-charging the battery twice and letting it set since it was overheating). Since I had never driven it before I didn't know that there was really that much wrong with it besides the idle which I didn't pay much attention to. It sat in my garage for awhile until me and a friend put in the new alternator (which took about 3 hours). I don't really know when I realized the idle but I would like to get it fixed. When the engine is cold and I push down the clutch it starts to die. It also idles at about 2100 RPM. Someone told me about this site so I decided I would ask how to fix this problem or any other problems that may arise. I've looked around and other people that have had the same problem have replaced the pcv valve but I can't seem to get mine off. I just want to know if there is something I can buy (like a kit) to fix this problem and get rid of all this vaccuum junk. I have also tinkered around with the carburetor to try to get the idle down. If I loosen this one screw on the left side of the carb the idle goes down but then it starts to die. So the idle remains at 2100 PRM. Thank you for reading this enormously long reply and for your help.

A20A1
08-12-2002, 11:51 PM
The fast idle screw is causing the high idle when the car is cold... the fast idle screw controls the fast idle speed. fast idle is around 2,000 rpm

The screw on the left side of the carb is the idle controll screw...
the idle control screw sets the highest idle speed when the car is warmed up. (idle is around 900rpm)

There is a black knob behind the carb that controlls throttle position which set the lowest idle speed. (lowest idle is 500 rpm)

I'm not totally sure on the idle speeds but they should be close... they normally vary with automatic and manual transmissions

rbeaud
08-14-2002, 10:13 AM
Originally posted by dj99
(According to the manual...)

Fast idle CAM (choke?) is engaged via the accelerator pedal. The fast idle unloader on the carb has two diaphragms controlled by thermovalve A in two steps. When the coolant temp is reaches 59F is stage 1 (fast idle), up til 131F is stage 2 (fast idle first step) and over 131F is stage 3 (fast idle off).

So to answer your question, there is no hose to turn it on. :)

If you are interested in troubleshooting the fast idle unloader system (looks fairly simple), I would be happy to send you the page from the manual. Send me an email.

I need to diagnose why my idle is stuck at 1800 rpm. Would you mind providing that info to me?

Cheers,

Roland

motoboy
10-01-2002, 05:40 PM
Thanks for the help. Nothing against Honda's because I love mine! But I don't know what they were thinking when they put in all of that vacuum junk. I just gonna live with this problem for now and wait for the engine to go out (since I have 188,000 mi.) and rebuild my own.