New Member
Sep 10, 2020
Denver, Colorado
2007 335i

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 rollers but the lady at the front said everyone will do OBD as long as there are no check engine lights present.

What I did to pass-

I was going to install a dp fix but found out the car already had it installed (I know it’s not supposed to be in there for long but it will come out ASAP). Mine was set to 5 O’clock.

Here’s a link for how to install dp fix with jb4-

Heres a pdf from burger motor sports on how to install without jb4 and with-

Reflashed my custom tune but selected the option OEM/Catted downpipes and turned off all burbles

Preformed the drive cycle necessary to have all emissions monitors complete. The process of how to do it is here-

I didn’t think I’d be able to complete the cycle because of the traffic in my area but I ended up finishing within 10-15 miles. I checked by having my jb4 off and had my wifi adapter connected and I kept checking codes to see which monitors were complete or not. I couldn’t get the Evaporative system to show complete but I knew this was ok. I called to see which monitors were allowed to not be ready and they said the only ones that will make you fail if NOT complete are Catalyst and O2 sensor.

This is which of mine were ready that allowed me to pass

After making sure the monitors showed complete I went in and they did the obd test and everything was fine.

I hope this helps a couple of you! I tried putting all the answers to the questions I had in this post but let me know if anyone needs help!


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New Member
Jun 26, 2020
Thanks for posting this. It helped push me to buy a single turbo, knowing someone mapped out exactly how to handle this scenario. I’m assuming others have referenced this post as well. 🤘