I had a bassani catback with offroad X-Pipe on my 02 GT. I passed emissions in cook county twice using the MIL eliminators from AM. Those are the only way i was able to pass. I tried the spacer trick but i couldn't get it to work. If AM tunes the car, they're most likely going to turn off the o2 sensors completely, to get rid of the cel. But that's an automatic fail if you take it to get tested. Stock tune and MIL eliminators are the way to go in my opinion.
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