Idle Speed Adjustment

[DBMaster]

I have been trying to adjust my idle speed up a bit to reduce vibration. I am not sure where the device is that boosts idle speed when the transmission is in drive, but it appears to be malfunctioning. The idle speed runs about 900-1,000 in park, but around 600-700 in drive. I need it a bit higher in drive so I either need to get it higher in park, or replace whatver part has gone bad that is allowing the speed to drop. I have had this car since it was new so I know that it used to auto-adjust. Any time I adjust the speed up with the screw on the throttle body the car seems to "self-adjust" it back down.

[DBMaster]

I am surprised but gratified that no one seems to know the answer. At least that means that I am not overlooking the obvious!

[88Accord-DX]

Unplug the electronic air control valve, check idle is in range. Adjust as neccessary. Turn ignition off, plug EACV connector in, remove fuse for 10 seconds.

[DBMaster]

Which fuse, the "Clock/ECU" fuse?

[DBMaster]

Well, duh, of course it is the clock/ECU fuse. When you unplug the EACV you get a check engine light so you have to unplug the fuse to reset the ECU. It appears that I was successful. Thanks, dude!

[dlr1989]

DBMaster, don't feel to bad, your in good company. I had to to the same "Well, duh" a few months ago when working on an idle problem. I fact I think I said exactly the same thing. I have had the car nearly 18 years and it just had not come up before. I guess that says something about the reliability of these 3rd generation Accords!

Well, duh, of course it is the clock/ECU fuse. When you unplug the EACV you get a check engine light so you have to unplug the fuse to reset the ECU.

[DBMaster]

Yes, they do seem to be bulletproof. I should have just looked this up in my shop manual. It's one of those things that I have done before, but not that often. It must be a combination of my age and how long I have had the car. You know you have had a car a long time when it has been so long since you performed a maintenance task that you forgot how to do it!

[89hondaSOHC]

Unplug the electronic air control valve, check idle is in range. Adjust as neccessary. Turn ignition off, plug EACV connector in, remove fuse for 10 seconds.

Where is this air valve? My cars idle is just between 1500-2000. It climbs to 2000 then goes to about 1000 and repeat.When the car wants to it has a steady idles but its at like 1100

[88Accord-DX]

It's between the fuel rail & intake plenum.

[89hondaSOHC]

to many posts sorry

[89hondaSOHC]

It's between the fuel rail & intake plenum.

thanks i will go try and find it

[89hondaSOHC]

It's between the fuel rail & intake plenum.

To many posts sorry

[88Accord-DX]

It's the silver part between the fuel rail & intake plenum (throttle body). He is a pic for example, to help see it.

[89hondaSOHC]

Is it this?

[88Accord-DX]

Yeah, from the yellow looking connector to the left. (got a little too much circled)

[Pico]

I'm throwing a Code 14 on mine which means a bad IAC Valve, anybody have any suggestions on how I clean this part out once I take it off the car.

[DBMaster]

When you remove it you will be able to see the two openings for air. They will be very dirty. You can mess around with some carb cleaner and an old toothbrush, but you will probably find you need to replace it like I did several years ago.

Also, you will need a new gasket. It's a funky o-ring shaped kind of like a pair of eyeglasses. It's cheap - even at the Honda dealer - if you can find it.

[2oodoor]

Use throttle body cleaner not carb cleaner. you could probably use the seafoam products actually

You can try checking your distributor timing and advance to to reduce vibration at idle

[Pico]

I'm gonna give a cleaning first and hope it goes well

[blh1983]

Ok, I guess my car just doesn't have an electronic idle control; or does it? So how do I adjust my idle speed if this is what it looks like on my car?? I'm confused about how I adjust my idle. Thank you!

[LX-incredible]

86-87 idle is controlled by a series of air bleed solenoids located in the black box. You can adjust idle by turning the brass screw located near the top of the throttle body.

[LX-incredible]

It's the silver part between the fuel rail & intake plenum (throttle body). He is a pic for example, to help see it.

That's one good looking engine.

[blh1983]

Thank you! I had an 87 Accord LX-i at one time and turning that screw would only turn up the idle not lower it so I didn't think it would work on my 86 LX-i either. The idle is now adjusted. But I have another idle related problem. My A/C Idle Boost Adjustment has no effect on the idle speed when the A/C is on. I'm running an EDM ECU could that be the reason? I've got my car idling at 900 RPM's but when I turn the A/C it idles at 550 RPM's and shakes violently, and the idle boost has no effect. Before I adjusted the idle she ran at 1000-1100 RPM's. Anyone got any ideas on why this might be? Thanks!

86-87 idle is controlled by a series of air bleed solenoids located in the black box. You can adjust idle by turning the brass screw located near the top of the throttle body.

[LX-incredible]

The AC solenoid is located in the black box, it is usually the one with the dirtiest filter. I remember it being all the way to the right. Clean the filter and check that vacuum is being pulled through the metal barb on the top when the compressor is engaged. If no vacuum, unplug the solenoid and check for voltage.

[blh1983]

From what I've heard the EDM ECU disables most of the stuff in the black box. If there's no voltage could it be that with my ECU that there isn't supposed to be? I will check ASAP; but first I will need to go and buy a voltmeter. Thanks for responding!

The AC solenoid is located in the black box, it is usually the one with the dirtiest filter. I remember it being all the way to the right. Clean the filter and check that vacuum is being pulled through the metal barb on the top when the compressor is engaged. If no vacuum, unplug the solenoid and check for voltage.