Usually being cammed is the biggest offender when failing emissions. That is depending on cam size as well. Even though your car is stock, There are quite a few variables that can effect emissions testing. O2's, EGR, trouble codes, long tubes, cats, etc. I wouldent think a mail order tune would throw it off too much. Whats the main reason you are wanting g a tune?. I only ask because you are not modding anything at the moment that would require a tune.

Be aware, after flashing the PCM, you will have to drive it for 50+ miles so your system readiness tests pass.

 

Everything stock but I will be doing a y-pipe and a muffle dumped at the axle and thats it for now.