[ap24la]

Hoping someone can give me some direction here to clear my CEL and get my 2019 m850i smog passed.

Car is currently on VSRF catless DPs and DME stage 2 tune.

I’ve been unable to clear the CEL long enough to pass smog because once the necessary mileage is driven, the light comes back on.

I’d like to add 200c high flow cats if possible but obviously want to be sure they will pass and remove cel.

Ideally no hardware change necessary though if at all possible.

Is it possible to simply change my tune to something like BM3 and permanently clear the code?

If not and hardware must be changed, I found these 200c high flows. Not 100% sure on CEL for these though https://german-car-accessories.com/p...45949964222686

[DrVenture]

I know a guy with catless DP and tune, who is a darn good mechanic and well-informed, he puts his original DP back on every three years for OBDII. The problem is that the O2 sensors will never report "ready" state, if the CEL is turned off in a tune.

High flows will get you to ready state, as the O2s exist. Whether they indicate efficiency, or throw CELs at random times, I don't know. Might get you past the test though.

My guess is you need both catted DPs and a tune that acknowledges the existence of O2 sensors.

[christianb5s4]

There are also CEL free 200 cell options, worth a look. But even then it depends on if a smog shop really takes the visual inspection seriously. Coding out a CEL is guaranteed flag fail.

Can't wait for the day this stuff ends in California.

[MaxVO2]

Originally Posted by DrVenture

I know a guy with catless DP and tune, who is a darn good mechanic and well-informed, he puts his original DP back on every three years for OBDII. The problem is that the O2 sensors will never report "ready" state, if the CEL is turned off in a tune.

High flows will get you to ready state, as the O2s exist. Whether they indicate efficiency, or throw CELs at random times, I don't know. Might get you past the test though.

My guess is you need both catted DPs and a tune that acknowledges the existence of O2 sensors.

****This has been my experience here in Maryland where we have emissions and a visual. They used spacers of some sort on the O2 sensors in addition to a tune that recognizes the O2 Sensors. I have had no CEL lights at all since the DP change with high flow cats.

I was told the O2 spacers would have to be replaced at some point if the car was driven enough. I've been good for some time now but don't really drive all that much. The spacers are inexpensive and easy enough to install.

I'm just happy to not have the CEL quite honestly. Have had other cars that were nightmares to get past our emissions standards here.

[pbonsalb]

Spacers don’t work and cheap 200 cell cats don’t work for stopping the CEL. Fabspeed or Redstar HJS 200 will but cost $3k. LEIB deleter will also work. Some report that some mini cat O2 spacers worked. I tried some once and they did not work. BM3 works to pass OBD2 plug in for readiness monitors if you can flash a tune. 2019 should be easy to flash. Flashing can void a warranty.