First off... if your base tune is in good order and you Cat is working you should have ZERO issues passing a 2 speed idle test. If you could post an idle and 2500 log that would help aswell.
What he said. I failed miserably, dead O2 sensor was the first reason. I put a wideband in there, Stephen helped me A LOT with the base idle tune. Went in and still failed but barely. So I took her for a nice hard long drive, and she passed with decent numbers.
I only had 94 octane in the tank and did nothing else
