Ever use and have luck with "Guaranteed to pass " auto emissions stuff?

I've heard of it working but first I'd try passing the test without it bec that's the best way to make sure all is okay.
Basically what I advice before any emissions test to occur is to follow these basic steps.
No1 always perform a oil change
No2 make sure that there is either a full proper check or a basic tune up of the spark plugs , sparkplug wires and air filter are performed
No 3 make sure if fuel filter hasn't been changed in awhile or on average once a yr have it changed asap
No4 be sure that the gas tank is atleast half full when the emissions test is performed
No5 make sure that the gas gap is tight
No6 pre-book emissions tests so you can have atleast 20 to 30 minutes of hwy driving directly before the test is done
No7 have a reliable mechanic or exhaust shop that you trust perform a free exhaust check
No8 be sure if that if there is anything found wrong with the exhaust that the mechanic show you the problem and explains the problem and cause fully to you
No9 pay attention to your vehicle and listen to the normal sounds it makes and always pay attention to the exhaust's odours or smells and colours
No10 make sure if you don't yet fully trust or know the shop that you get a second and even third opion before spending any money on repairs or parts

Hope that helps and best of luck.By the way I think if you change the oil and oil filter and add some Lucas oil treatment to it you may find that helps alot.
If you can someone to check and clean , regap or replace the spark-plugs and wires , plus clean the ignition coil connections with a small wire brush that may help a great deal too.
What I do personally is clean or change those things I've mentioned and then I see if the engine runs better and exhaust looks or smells better and I highly believe in Lucas oil treatments or additives so I use 25% or 1 lite of Lucas when I change my oil.
One last note if they say that the catalyitic converter is shot , shop around bec some shops will replace it alot cheaper for you and keep in mind if cat converter is indeed shot that the o2 sensor should be replaced too bec it caused the cat converter more then likely to fail.
Happy Holidays

Run your tank dry, then fill up with GOOD gasoline, not the cheap stuff. You shouldn't have a problem with smog problems if you've taken proper care of the vehicle. You can also use E-10 or E-15 gasoline to pass the smog checks. It's cheaper and you don't have to do anything special with it. Have you had other problems with the car? If not, try passing without the garbage in the tank. If the car uses oil excessively it won't pass no matter what you try.

Yeah, i've used that stuff. Just follow the instructions. Put some in your tank and fill it up, and drive it for at least 30 minutes before the test. I used that stuff when I was in a smog check state, and it worked great.