Resetting idle after CAI install

[JeremyR]

Greetings,

I've been lurking around 3geez for a while--it was here that I was inspired to install a cold air intake into my `87 Accord LX-i (A20A3), being the tinkerer that I am.

Well, unfortunately it seems that I'm not that good of a tinkerer, as I turned a perfectly working engine into, well, let's just say that it could be doing better. After reconnecting numerous vacuum lines (using a handful of tee fittings since the stock intake plumbing has a number of vacuum nipples that the CAI doesn't), I'm not able to get the idle quite right. I'm pretty sure I don't have any vacuum leaks, although I can't rule that out entirely.

In the process of tinkering, I've actually been able to get the idle close to where it should be: in Park or Neutral (did I mention this is an automatic transmission?) with the A/C on, idle is just under 1000 RPM; with the transmission in gear (A/C on or off) it's around 800. In Park with A/C off, it's around 1200, sometimes closer to 1500 (which is a bit high). But I should mention that I've only been able to do this when vacuum lines 17 and 18 (which lead to the "black box") are disconnected. When they are connected, the engine stalls when the A/C is engaged and/or the transmission is put into gear.

I should further point out that the transmission doesn't even have to be put into gear--if the lever is nudged slowly, the engine stalls well before the gear would have been engaged, as if some maladjusted idle control were kicking in. Also, while I'm thinking about it--what I believe is the A/C idle adjust screw doesn't seem to have any effect on engine idle.

This doesn't seem to be normal behavior after swapping out the intake plumbing, or I would guess I'd have read about it somewhere. Since I haven't, I wonder if I've done something wrong? Is there anything I should specifically look at? (Perhaps not all lines leading to the stock intake are vacuum lines?)

Cheers,
Jeremy

[frantik]

weird.. i dunno bout 86/87 but on 89 there is only the EGR hose to the intake.. no vac lines

but anyways you can reset the ECU by removing the ECU fuse for a few seconds or just disconnecting the ground to the battery if you dont care bout your radio stations

[ghettogeddy]

i did not re connect any when i did my short ram and i have no idel issues

[Demon1024]

I can only think of one line going to the air intake and it come from thew valve cover. is this what you connected to other hoses?

[nswst8]

You will need to post a picture of your set up.

Did you disconnect the IAC 2P connector before you adjusted the idle. Its been my experience that the IAC needs to be cleaned this is what adjust your idle under load.

But 1st you need to ensure you have correct timing. then adjust your idle.

[Accordtheory]

You need to break out the factory service manual and understand where all the lines go/what they do. It's stupid, late 80s over complex crap, but still not hard to understand.
Newer cars are usually much simpler.

[JeremyR]

Thanks for your replies, guys.

I should be able to post a pic tomorrow. It's a pretty straightforward setup.

I took the car on the road for the first time today since making various adjustments. Before I did that, I was able to set the idle down by a few hundred RPM--although I have no idea why. Upon a cold startup, it was idling at about 1800, so I dialed it down. Checked the idle in gear and with A/C on and it was fine. Let the car warm up and did the same thing--still fine. Drove around for a few miles--no problems. Turned the car off. Started it a few minutes later. Engine still idles and runs as it should.

This is still with vacuum lines 17 and 18 (the black box lines) disconnected. If I'm reading the (Chilton) diagram correctly, 17 connects to the EGR control solenoid valve, and 18 feeds the A/T idle control solenoid valve and the fast idle control solenoid valve.

At least one of the other vacuum lines, which I did reconnect, connects to the idle control solenoid valve (which is mounted on the driver's side wheel well). Apparently this is present on 86-87 Accords and 84-87 Preludes. 88+ cars apparently have an Electronic Air Control Valve (EACV), which explains why the newer 3G's have fewer vacuum lines.

Someone mentioned timing. I didn't check it, but there wasn't any evidence that the timing was off before. Still, wouldn't hurt to check it.

And where is the Idle Air Control (IAC) valve? That's something I haven't come across yet.

Thanks again--you guys are great.

Cheers,
Jeremy

[Demon1024]

you don't have an iacv on yours.
there's an online manual too. it's by paul i can't remeber exactly where some one will have it bookmarked tho