Im in maryland... Dont know why i failed... i have the stock main cat and air pump still functional and i have a jdm downpipe. I bypassed the stock fuel pressure solenoid and am running straight off the manifold... Should i have passed?

 

How many miles on the car (and the cat)? Was the cat hot when you took it to get tested? A cold main cat with a downpipe might not make it. I don't know what the effects would be from bypassing the stock fuel pressure gauge...
One gallon of denatured alcohol to 1/3 tank of gas should get you to pass if you need to in a hurry (it worked for me-- DP, high flow cat and CB), but you should try to find out exactly why it failed if the stock cat was hot. That's all I know.

 

I am in DE and I passed with a Downpipe on. You should give it a hard run before you go to get it tested, make sure you get all of the carbon buildup out of the pipes. How many miles do you have on the car? Your main cat may be bad.

 

Go to your local auto store and buy some of that emissions pass fluid stuff. It works wonders.

 

car has only got like 50k on it... and about 3k on the new motor. my hc was 1320 ppm where the standard is 220 ppm and my co was 6.69 pct while the standard is 1.2 pct...

I ran the car before I brought it in but they made me sit a while so it probably cooled down a bit. Im getting a haltech soon... if i run it lean and (retard or advance) timing... and put in new plugs think that will work??

and what of this denatured alcohol stuff.. Will that hurt my car? and where can i get it?

 

I'm in Oklahoma and we did away with any kinds of inspections a year or two ago

 

No, it wont hurt your engine. It's not great for the engine or anything, but it shouldn't cause any damage. I think that it removes carbon buildup in the engine, and it burns very clean.
Before the test, drive the hell out of your car to heat up the cat. Then when you are about a 1/2 mile from the inspection place, put the alcohol in (0.5-1 gal of alcohol to 1/3 tank of gas). Right after the test, fill the rest of the tank with whatever gas you normally use. Then, just to be safe, don't boost too hard untill it all gets out of your tank (by the next fillup or two). You can get it at any hardware store, it's in the solvents section.

 

You aren't going to pass emissions after it cools down. You need to have them test it while your cat is hot and right after you have just driven it hard. If they give you grief bout this, explain to them that a cool car doesn't simulate real world operating conditions.

Good luck and I hope that this advice can help some.