[HootisTigglebits]

Has anyone done this successfully on a 2017 M240i? My state just checks the computer to see if there’s any trouble codes set and that the system is ready. Since I have a catless downpipe my catalyst system and downstream O2 system just says “unready”. Figured I’d see if this actually works or if I need to put my cat back on.

[n55david]

Originally Posted by HootisTigglebits

Has anyone done this successfully on a 2017 M240i? My state just checks the computer to see if there’s any trouble codes set and that the system is ready. Since I have a catless downpipe my catalyst system and downstream O2 system just says “unready”. Figured I’d see if this actually works or if I need to put my cat back on.

Extremely hit and miss.. most of the time you'll have issues

[kamilbaran]

Originally Posted by HootisTigglebits

Has anyone done this successfully on a 2017 M240i? My state just checks the computer to see if there’s any trouble codes set and that the system is ready. Since I have a catless downpipe my catalyst system and downstream O2 system just says “unready”. Figured I’d see if this actually works or if I need to put my cat back on.

What I am doing with my catless F80 is keeping my stock downpipe and swapping back to the stock downpipe and flashing to a stock tune. There's also some places that will generally pass you as cash is king. For my M240 to evade the emissions issue since I don't want the headache of that process I am going with a high flow cat, I can still get to stage 2+ but depending on what you're reaching for the Hi flow cat may be restrictive? You are able to put a spacer but finding a shop willing to do it is hit or miss and doing it the right way yourself as someone said is also hit or miss, but it wouldn't hurt to try it is possible.

[seanroberts000]

I would never try to cheat emissions, but IF I DID, I would have installed this:
https://www.fortluft.com/fortluft-o2...ler-90-degree/

A "friend" verified they never remove their DP back to stock now and never throw CEL. Just remove the tune back to stock, verify with OBD monitor, and go in for the inspection.

That particular 90° defouler is OOS, but there is enough room for the straight bung. Probably well worth the hassle of changing DP every year