Just signed up here, been watching for a while, I own a 2003 LS430 and a 1994 GS300, I just failed smog with the GS today, I failed HC and CO:

HC: 15mph = 124 max 81
HC: 25mph = 110 max 47
CO: 15mph = 0.78 max 0.47
CO: 25mph = 0.87 max 0.44

The CEL doesn't come on, the exhaust smoked during the 15mph test and a little during the 25mph test, I just bought the car a few weeks ago, since purchasing the car I've changed the oil, ran Lucas fuel treatment in the tank and ran 6 ounces of Seafoam to clean things up a bit, what steps should I take to get this thing to pass, it has 138k on it.

There may be a code even without a CEL. Is it running rich? Try pulling the code to track down the culprit.

we used to have our own smog test only station. too bad we sold it, if we didnt i could have probably passed you

How do you pull the code on a 1st gen GS?

I performed a tune-up, new plugs, wires, pcv valve, air filter, cap and rotor, 3 part seafoam treatment, in gas tank, in oil for 100 miles and the other one that makes the car smoke, changed the oil to 10w40 synthetic and added Lucas Engine Treatment.

HC 15mph: 81 max / 78 Pass
HC 25mph: 47 max / 116 Fail

CO 15mph: 0.47 / 0.38 Pass
CO 25mph: 0.44 / 0.39 Pass

Things on my to do list: Check the timing since the smog tech didn't and clean the egr valve, any other ideas?

Though it is not very well written, the following page explains how to pull the code.

http://www.troublecodes.net/Lexus/

They should not have combined instructions for OBD1 and OBD2, since you need a scan tool for OBD2. If your car is pre-1996, jumping E1 and TE1, as shown in the graphic, works. If its 1996 or newer, you need a scan tool.