Lean running problem

[BoxFan]

And Hello! Good to be a part of this community!

I recently bought a '91 3S-FE 5-speed Camry. It needed some front end work, and still needs some mechanical work ... and it looks really rough, but the price ($300) was right. It's also got a new clutch.

Anyways, I'm trying to get it to pass emissions. My girlfriend took it to get it inspected, and they say it failed by having high hydrocarbons. I've heard the best way to get it to pass is to put additives in the fuel and run it for a while, change the spark plugs, and do a fuel induction cleaning service. I replaced the plugs and wires (and distributor cap. heh), ran the induction service, but I can still smell the car running lean. it gets really good gas mileage though. :P

The plot thickens though...

While I was running the induction service, I noticed a plug that was unplugged... I found where it went, and my dumb ass plugged it in while the car was running. The idle started to lope. It would idle high, then dip down and go to 400 or less RPM, then go back up. I unplugged the plug. Normal idle, but still running lean.

The plug goes to what looks like a vacuum control solenoid or something like that on the bottom of the throttle body. It's a little white (well, yellow) plastic thing about 2 inches tall, and has two connectors that go to what look like vacuum lines, and then it's got an electrical plug. It looks like one of those vacuum lines goes to the charcoal canister...

I don't know much about emissions (please if anyone can point me to a good place to learn, I'll eat that stuff up), but does that mean the little part with the plug needs to be replaced, or does it mean the charcoal canister is clogged or something that will cost me a lot of money? The car runs great now, it just smells funny and won't pass emissions. Although I don't know, I haven't tried getting it inspected since I tuned up the ignition and did some minor fuel tricks.

Any help with this problem would be great!

[TBayToyotaBoy]

I'm not sure yet which vacuum line you're talking about, I'll have to look on my 3sfe tomorrow...

In the meantime, just a tip: any time you're scheduling an emissions test, make sure the garage you select will let you drive right in and hook up for the test. The best idea is to run the vehicle on the highway for awhile JUST before undergoing the test. As in, exit the highway and drive right into the garage bay. Here in Ontario many of us have found that's the best way to ensure a pass on emissions testing.

[BoxFan]

Okay, i'll make sure to do that when I try to get it inspected next.

And the vacuum line basically goes to a little yellow ... thing with an electrical plug on it. It's on the bottom of the throttle body, like right under the butterfly. It's not the TPS, but it is right there.

[disregard]

was it an unplugged vacuum line or an electrical plug ?

[BoxFan]

It was an unplugged electrical plug. I was running some fuel induction treatment through the car, and as I was waiting for it to all get sucked in there, I noticed an electrical connector hanging around there. I saw where it went, that little vacuum thingy, and plugged it in. It promptly began dipping in RPM, then rising then dipping, etc. I was driving around after doing the treatment, and eventually had to stop somewhere and unplug it so I could drive the car without stalling it.