emissions

Hi All: After scouring the BMW-related forums, I have been unable to find definitive answers to my emissions-related questions regarding my N54 with catless downpipes. I understand that the answers to these sorts of questions can be specific to a particular vehicle's problems and...

Hey everyone ! Im due for an emissions test soon and looking for some advice on how to pass properly. I have a temporary 30 day permit before they fail me :( Here are some things that I know I need to do. Please let me know if im missing anything else Take back up of stock tune via MHD (...

Hey! I made this post to hopefully help out another single turbo n54 owner looking to pass emissions. Information on my car - 2007 335i N54 On3 single turbo kit Manzo catback exhaust E60 mix on a custom tune (jb4 + mhd bef) I am in Colorado, typically for a 2007 they would do the test on the...

No idea what the hell is causing this anymore. The codes were involving both post-cat o2 sensors and pre-cat o2 sensors with lamba/mixture errors. I replaced both back o2 sensors and the front o2 sensor that was giving codes, they still appeared. At this point I assumed it had to do with my car...