Here's the trick I used to get my "gross poluter" (1978 Mercury) to pass every time.
Go to your local hardware store and buy a gallon of denatured alcohol. Run your car until it is almost out of gas. Just before you take it to the sniffer test, pour in the denatured alcohol. The alky lowers the fuel's stoich A/F ratio which does the same thing as leaning out the engine.
Go fill up your tank to the brim with regular gas as soon as you're done and drive it a bit to get some of the unadulterated gas all the way through the fuel system and you won't have to worry about rotting out rubber bits.
This way you can get your car inspected and go about fixing whatever the problem is at your own pace!

Good luck.