So newer cars typically have an Idle Air Control (IAC) valve that on demand, (A/C, parking lot power steering load, additional power load, etc..) will increase the idle to stay within the specified RPM range.

Does my Honda have one? Or is it a solenoid for each load that individually increase the RPM's per the load they are associated with. My car idles great in P and N. When I place the tranny in gear, I loose about 300 RPM, down to the prescribed ~750-850 RPM range. Nothing seems to attempt to "add" RPM's at that point. If I further irritate matters by turning on the A/C, I loose another ~175 RPM's, bringing the sum total to well south of the prescribed amount. Now it SHAKES. If I place the selector in P or N, again I'm in the prescribed RPM range.

So after a decent inspection of basic engine control operation, I'd like to focus on the symptoms and work my way backwards to the problem. Sorry for the long post, I'm more thorough than your average bear ;) (Oh and I'm an ASE certified mechanic, just not my trade)

Yes, the LXI has an idle control valve. In Honda speak it is called an "Electronic Air Control Valve" if I remember correctly. It is attached to the front (front of car) side of the intake manifold. It has two small coolant lines that run to it and a control wire or two.

If you haven't already found them I would recomend the www.3geez.com forums. They are specific to the 3rd generation and older accords. Much information and help to be had there.

CPUNeck:

On in the injected engines, as DLR2009 points out, there is a "step up" valve attached to the front of the intake manifold (mine has a white cap, involving a tension spring, on the underside). It governs "idle" mode when you engage the A/C compressor. It involves two (2) VACUUM lines, NOT engine "coolant" lines.

With your AT in "Drive/Reverse," with A/C engaged, you should see a tach reading of 750 RPM, plus-or-minus 100 RPM. You may also have to fiddle with the (basic) idle adjustment. As you are likely aware, it's located on the lower side of the throttle body, and takes a small, flat-blade screwdriver...

I have a great dislike for incorrect information, especially when I am the one who provided the incorrect information. Wardnr is correct, the lines running to the EACV are vacumn lines.

I have a great dislike for incorrect information, especially when I am the one who provided the incorrect information. Wardnr is correct, the lines running to the EACV are vacumn lines.

However, on 4th gen and up, the IACV (same as EACV) has coolant lines running to it.

Dlr2009:

I wasn't necessarily, and per se, correcting you. The A/C "step up" valve (on the front of the intake manifold) DOES involve two (2) VACUUM lines. The "idle control" solenoid (mounted on the driver's side strut tower, just in front of the wiper motor) ALSO involves a couple of VACUUM lines.

However, the "idle control" valve (mounted on the backside of the throttle body) involves a couple of COOLANT lines. In that regard, Sir, you are absolutely correct. It has a wax-coated plunger which often sticks/jams, causing idle issues.

I am quite confident in what I say....as I have (personally) replaced ALL the above on my own car.

I should also point out that there are some differences on the 1986-1987 injected engines versus the 1988-1989 injected engines, respective to "idle control" hardware. I am better-equipped to discuss the particulars on the 1986-1987 "A20A3" engine, given my (16-year) ownership history and experience.

Awsome, I'll be tearing most of the accouterments off the intake since there are so many, looking for coking/gumming and checking for functionality. Seems the only identifiable item on the drivers strut tower is the injector resistor ??:dunno: There is a dash-pot on the drivers front corner of the intake plenum. Looks to be vacuum operated.

I'm still not certain of the EXACT engine I have. Seems there wasn't that many auto's made that were LX-i. (But I don't know that for a fact). I say this because I've received different information concerning how to time this thing. I've got three marks on the T/C, and a red/orange dot. (I haven't used a timming light in 15 years) and have forgotten how the degree knob on the back of it plays a roll, so quite likely my car is out of time, and it's all user error:D

The idle is better, but I'm a perfectionist, so I'll keep beating at it until its right. I've also noted it requires ~5-15 additional RPM to start. (takes a second longer), and I have a hesitation/miss off idle. This hesitation is noticeable from stop, or cruising and the T/C locks while under light acceleration, if you hold it you can feel the miss. I'm hopping the timming is to retarded. Thanks for all the help, and detail.:thmsup:

CPUNeck:

On the 1988-1989 LX-i cars, they may not have the "idle control" SOLENOID of the earlier LX-i engines. I'm really not sure.

Cleaning out the intake manifold is likely a worthwhile endeavor, but a major ordeal to remove/reinstall it, given the extremely poor access to the nuts which attach it on the bottom side. Typically you remove/install the intake with the cylinder head removed! I know this from personal experience, having personally rebuilt the engine in my trusty '86.

While off the car, I washed my intake manifold out with carb cleaner/lacquer thinner and several toothbrushes. It tends to carbonize/gum over with deposits caused by the PCV valve. Good oil and (reasonably frequent) oil changes will typically help reduce deposit buildup in the intake.

Setting the ignition timing is not a big deal. On the 1986-1987 LX-i cars, it is 15 (fifteen) degrees BTDC, plus or minus two-and-a-half (2.5) degrees. The red mark (on either the flywheel or T/C) is TDC. The white marks just above and below the red mark are your advanced/retarded settings, respectively. There is a "pointer" on the block you line said marks up with. Per my factory service manual, I set my timing exactly at 15 (fifteen) degrees BTDC. I typically set ignition timing with the engine at NOT (normal operating temperature) with my (manual) trans in "Neutral." "Park" or "Neutral" is fine for an auto tranny car.

I use a Sears Craftsman timing light. Connect it to each post of the battery, with the "pickup" attached to cylinder #1 (number one) high-tension (spark plug) wire. Firing order is "1-3-4-2," as is the case with most I4 engines.

Disconnect the vacuum line on the distributor (vacuum advance unit) and plug it off while you are setting the timing.

With the distributor bolts SLIGHTLY loosened, shine the timing light through the hole in the block at the front, and slowly twist the distributor. When you get the MARK lined up with the POINTER, lock the distributor down. That's all there is to it.

The injected engines use the "Tec" distributor. The carb engines use distributors made by Hitachi, Toyo Denso, and others (as I vaguely recall). Unless your distributor is faulty in some way, you should seldom have to adjust the ignition timing. When I set mine some four (4) years ago, I haven't touched it since. The car runs like a $20,000 Swiss watch! :)

You are quite correct about the lower production numbers (er, rarity) of the fuel injected cars. While I don't have a thorough, specific breakdown, HMC produced 700,000 Accords for (model year) 1986, with less than one-third being "LX-i" models. This means I have one of approximately 233,100 fuel-injected cars they produced. Total Accord production for 1887, 1988, and 1989 are one (1) million units per year. I do not have a production breakdown respective to the injected engines versus the carbureted engines for said years. If HMC publishes this information, I do not know how to obtain it.

To the best of my knowledge, ALL fuel-injected engines are coded "A20A3" for all four (4) years. Code translation: Two-Liter engine family, fuel-injected, USDM (United States Domestic Market). 1986-1987 "LX-i" is rated at 110 bhp. 1988-1989 LX-i" (and "SE-i") is rated at 120 bhp.

Hardware upgrades on the 1988-1989 "LX-i" (and SE-i) engines include a "Tri-Y" exhaust manifold featuring two (2) oxygen sensors, a different intake manifold, different camshaft, and different external sensors/controllers.