Dumb Dumb

you only have two o2 sensors, they are both before the catalytic converter, and are the same part number/price per side. i used to work for autozone and know for a fact there computers seem to have some trouble recognizing this, as it says that for all the cars. the people at autozone probably dont know a whole lot about cars, as there job is to sell parts not know what they are selling. but u only have two and they are close to the collector flange, on the midpipe. i have seen them cause some driveability issues when they were bad but never anything like this. i dont know if that is all of ur problem, but it could be partially the problem, combined with a mail order tune, it could just be the prob. the mail order tunes are supposed to be good tunes, but not dead on accurate. u wont get a perfect tune without a dynotune with a/f ratios

It's the E cam soem people have reported the same issues even after installing mail order chips. Not that the chips are bad just without a dyno telling you what the eec likes in your car it's hit ir miss.

a dyno pull with a wideband will tell you everything you need to know. when telling a chip maker your combo over the phone or through an e-mail they can approximate what you need, but even still, the results will vary from car to car. gewt on the dyno with the wideband o2 and let us know what it comes up with.