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Old 09-08-2012, 06:28 PM   #6
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Join Date: Jun 2008
Fan#: 57268
Location: Williamsville, NY
What I Drive: 2004 Pitch Black ZTS 2.3 5spd.

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FWIW, BC's got the right idea!

it's been discussed in the "tuning" forums - IF both cat sensors are working properly, the 'downstream" one needs to see "cleaner" exhaust than the "upstream" one to let the computer know the Cat is functional.

SO, 'cheating" by moving the downstream further out of the exhaust flow, like by screwing it into a "spark plug anti-fouling" adapter will "fool" the computer, letting you "pass" emissions testing....

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