Help needed - high idle problems

[sunderland]

First, I appreciate all the help I have already received from the expertice on this website.

I am still experiencing high idle (2200 rpm) on hot days (85 deg +) after the car is warmed up. A new twist I noticed now is that sometimes when it is idling below 1000 rpm it will jump to high idle if I turn the air conditioner on.

I have read multiple idle threads on this website, replaced thermovalve A, replaced carb base gaskets, checked coolant level, bled coolant, check pcv valve, checked for vacuum leaks, and sprayed linkage with carb cleaner.

Any ideas are much appreciated!

[sunderland]

Just tested throttle controller -- it seems O.K. Then checked A/C idle boost. It was holding idle very high, so I disconnected vacuum line #21 and that allowed engine to idle normally.

I'll follow the manual and check the A/C idle boost diaphram and solenoid.

[TheDaveler]

try pulling the gas pedal up when idle is high and see if your idle becomes lowered. If it does lower the idle then id say its your throttle return spring or slack in a cable somewhere.

[stevenr816]

i also have the same problem, my car idles at 2k+ but if it goes under that it usually dies. i've replaced the coil, distributer, wires, plugs, rebuilt the card and head, compression test, i dont have the ac hooked up so that doesnt matter, i've pulled on the gas pedal that doesnt do anything sooo.......... i also need help!

steven

[MfrDhRacer]

my accord does that every once in a while. just tap the gas slightly and it should jump down. or maybe your choke is sticking.

[A20A1]

https://www.3geez.com/forum/showthread.php?t=46572

[lostforawhile]

mine is doing something like this,and driving me crazy, somedays it won't idle,and somedays the idle won't come down,today oit say there and reved itself from idle to 2500 rpms over and over,I am very familiar with this carb and I still can't figure it out. i'm getting a new carb in about another month,but got to fix it in he meantime

[lyltoy]

try pulling the gas pedal up when idle is high and see if your idle becomes lowered. If it does lower the idle then id say its your throttle return spring or slack in a cable somewhere.

I am new to these cars and the forum. I just got an '87 LX and it is having a high idle problem, and just as you said when you pull the pedal back up the idle lowers again. I have adjusted the throttle cable and it is still having this problem. Where is the throttle return spring located so that I can check that? Thanks in advance for any help it is much appreciated.

[sunderland]

I think the throttle return spring is on the passenger side of the carburetor. Take the top hat off and you should be able to find it. BTW, my high idle problem has gone away, although I don't know exactly what the problem was. Like A20A1 and Kabuki say, check vacuum lines and diaphrams. I did change out a thermovalve and that seemed to have helped a bit.