dquiles07

Hi everyone! I have a 2008 IS250 and I have exhausted all avenues and I'm reaching for your feed back, hopefully you may have come accross this and found a fix or you can point me in the right direction.

The car has a sputtering when it changes to 3rd gear during acceleration. 02 sensors have been chaned, new sparks plugs, new coil packs, and new MAF sensor. I have also added fuelsystem cleaner 2 bottles in fact, air filter is cleaned, also cleaned throttle body. I do have the following codes still P0031 and P0051 but that is because I have catless racing headers, so to make the story short, my car still sputters/ hesitate. I'm open for any suggestions, advice, and fix to this madness. Thank you in advance.