How to pass emissions with catless downpipes

[2015f82m4]

Originally Posted by TakeOne

Just wanted to take a minute and say THANK YOU to this thread.!
It’s great when i can share something with the BMW community, but even more gratifying when I takeaway something from you guys.
This thread gave some incredibly “useful tips” (won’t say which ones I followed) such as helpful apps to download, clearing codes, getting the car in a “ready state” etc…
BimmerLink, along with the Car Scanner App mentioned earlier in the thread ,worked flawlessly with the Veepeak adapter to find the “sweet spot” when things were good to test. Thanks again BMW family.

No problem man! Feel free to follow me on IG @smurf.m4

[TakeOne]

Originally Posted by 2015f82m4

No problem man! Feel free to follow me on IG @smurf.m4

Followed

[horsepower_and_hounds]

Originally Posted by 2015f82m4

No problem man! Feel free to follow me on IG @smurf.m4

Pretty damn good vid..... but what about a bimmerlink vs that car scanner app? You threw it out there but what are the pro's n con's of it vs Bimmerlink

[horsepower_and_hounds]

Originally Posted by JD1100

How can they see the main cats with the shield in place ?

You can see then easily on a lift with a small flashlight..... if they check

[TakeOne]

Originally Posted by horsepower_and_hounds

Pretty damn good vid..... but what about a bimmerlink vs that car scanner app? You threw it out there but what are the pro's n con's of it vs Bimmerlink

Thanks for the feedback! I'll be as honest as I can. The Car Scanner App was REALLY easy and user friendly for the "emissions live monitoring". It was right there in your face and easy to see. However, the code clearing was a mess, cumbersome, and didn't always work.
Whereas BimmerLink I had a little harder time trying to make a custom "live monitoring", as that aspect wasn't very intuitive…
BUT, BimmerLink reading/clearing codes, was super easy, fast, and always worked…every time. That's why I used both in conjunction. Hope this helps

[Groganrocket]

Originally Posted by horsepower_and_hounds

You can see then easily on a lift with a small flashlight..... they check in NC

I'm in NC and they don't do emissions here in Chatham county they stopped that 2yrs ago. Thanks GOD

[marauder1]

Originally Posted by horsepower_and_hounds

You can see then easily on a lift with a small flashlight..... they check in NC

That's why I. Always go to the smaller shops that don't have a lift for emissions and safety. Most are too lazy to jack up the cars when they're lowered.

[chrison600]

Greetings everyone. I've been trying to solve this issue electronically without success, so wanted to post my attempts and results to see if anyone out there has advice or has had success with an electronic solution. I have several different types of defoulers, but thought it would be more "elegant" to defeat the codes electronically. Also, getting to the sensor locations on my pipes is difficult so I'm also being a bit stubborn (lazy?).

I purchased used sensors and a DME harness from a crash car so I could have the harness connections. My desire was/is to implement the electronic solution with factory harness connections to make it more easy to attach/detach. Basically I'm building an inline signal modifier using factory harness parts.

The first solution I tried was the area seventy four modules. I purchased two, wired them up using the factory extensions, and the car still manifested codes. However, rather than inefficiency codes, it was a combination of four codes for lean/rich condition. So the modules were impacting the voltage curves, just not in a way that prevented codes.

Then I purchased an assortment of resistors and capacitors as well as a "breadboard" and a few other basic electronics prototyping items. My intention was to try to build an "RC" circuit as you can find in various online posts (essentially it's a low pass RC filter like used in the audio world).

I rewired my harnesses such that the sensor heater circuit wire pair simply bypassed, and the sensor voltage circuit wire pair were jumpered across the breadboard. Theoretically that allows me to try any combination of resistors and capacitors without having to do soldering.

I'm not convinced that the breadboard solutions have actually been built correctly, but I've done rudimentary multimeter testing before running them on the car. I've tried the following combinations:

> 1MOhm resistor interruption on the + with a 1mFarad cap crossing + to - after the resistor
> 1MOhm resistor interruption on the + with a 4.7mFarad cap crossing + to - after the resistor
> 1MOhm resistor interruption on the + with a 4.7mFarad cap crossing + to - after the resistor AND a 1MOhm resistor crossing + to - with the cap (This was basically an attempt to add a "voltage divider" to the circuit)

All three of these combinations resulted in the reading going to 1.275v and remaining. I'm assuming that 1.275v is the max on the scale. I also ran a voltage test with the sensors simply disconnected, and the voltage went to 1.275v and remained, so essentially my breadboard circuits were doing nothing.

Currently I'm waiting on some solderable PCB materials to arrive so I can try some circuits that are actually soldered. I felt like this might be a better way to prove/disprove circuit designs without the variable of the possibly flawed breadboard connections.

In any case, if anyone has attempted electronic measures and had success, I'd like to learn about them. I've done a bit of homework on these sensor circuits in general and have a better understanding of what the DME wants to see, but it's not crystal clear, and I think that's by intent. There are some other commercially available solutions, but I haven't tried them yet. There used to be a product in the Mustang tuning community that was basically an inline harness solution, but that seems to be obsolete/unavailable now. I see some indications that something happened to the measurement circuit design or algorithm around 2006 that may have made it more difficult to defeat with a basic circuit. That may be instructive.

[Bettertomorrow]

Originally Posted by sicck_m4

Anyone running MHD? I noticed o2 sensor and EVAP monitors were not setting with flash tune. Do I flash back to stage 0 or flash back to stock(long write) to enable the monitors? Thank you in advance!

I asked MHD and they told me to flash back to stock, not stage 0. I got about an year and half until next emission. My plan is to drive by one of van-sniffing places several weeks prior to inspection if I can, hope it can pass with stock DP (no plan for catless DP). If that doesn't work, guess will have to revert to stock, pass emission, and revert it back to whatever stage I will be then.

[petertheplug]

Does anyone know how to remove the two sensors? Can't find a guide or clear instructions anywhere. There's pretty much no clearance to turn the oxygen sensor tool

[TopJimmy]

Originally Posted by petertheplug

Does anyone know how to remove the two sensors? Can't find a guide or clear instructions anywhere. There's pretty much no clearance to turn the oxygen sensor tool

You should remove the DPs first before removing the O2 sensors, this way you don't crunch or twist the wires.

[11LMBiSTT]

Originally Posted by petertheplug

Does anyone know how to remove the two sensors? Can't find a guide or clear instructions anywhere. There's pretty much no clearance to turn the oxygen sensor tool

You need to unplug the o2 sensors and then uninstall DPs. Once DPs are out, you unscrew the o2 sensors.

[Info@mad-us.com]

Some good info in here.

[WordOnRoad]

Has anyone played with the catted/catless options when flashing with MHD?

I recently had some issues with my F80 and the vehicle was flagged by the MAC center, which in hindsight was my fault. CAT monitor came up as unsupported vs. not ready.
Just a bit antsy to tune it after taking delivery. I'm hesitant to tune/go FBO now, as getting flagged again for a CAT issue would suck and require removal of parts etc.

I realize we can get away with one not ready, which brings me back to my first question. Does checking the catted option with catless DPs trigger not ready?

I suppose the defoulers on the DPs is a viable option, but I've never had to do that in the past.

I've used MHD on my E90 (FBO) and my E70 (all stock) and never had an issue.

Vehicle's are registered in MA for reference.

[Wanted_M]

I bought this to try it out, delivery Monday from Germania. Connects via FEM canbus.

https://www.awron.de/en/produkt/awro...ung-m4-cs-f82/

https://www.awron.de/wp-content/uplo...82-F83-F87.pdf

[tomlong]

I've been passing emissions with catless downpipes for 2-3 years now. As an Ecutek user, I just make sure I roll up to the DMV with my OBD Readiness parameters all showing green across except for one section, no CEL, and you're good. 🤷*♂️

[Info@mad-us.com]

Originally Posted by tomlong

I've been passing emissions with catless downpipes for 2-3 years now. As an Ecutek user, I just make sure I roll up to the DMV with my OBD Readiness parameters all showing green across except for one section, no CEL, and you're good. 🤷*♂️

You will always have one but most states allow it so

[M4_85]

Hey guys. I tried using the oreilly o2 defouler just like the op stated and after 15 miles, cel came back on? Any ideas?I live in NY. I stacked the 2 and put the stock tune back I have ar resonated dp and still got the cel, I'm wondering if something more like a "mini cat" like this one…

[mapster37]

Originally Posted by M4_85

Hey guys. I tried using the oreilly o2 defouler just like the op stated and after 15 miles, cel came back on? Any ideas?I live in NY. I stacked the 2 and put the stock tune back I have ar resonated dp and still got the cel, I'm wondering if something more like a "mini cat" like this one…

Ive been running these on the post cat 02 sensors. I have arm catless dp, no ck engine light for me yet....knock on wood...

[M4_85]

Seems like the oreilly ones work with no catted dp but has anybody tried resonated, I'm thinking I need the other defouler maybe

[deemack79]

I'm running arm resonated catless dp's. Never had a CEL and been running like this since Oct.

[M4_85]

Originally Posted by deemack79

I'm running arm resonated catless dp's. Never had a CEL and been running like this since Oct.

Guess I just have bad luck haha. I am getting p0420 and p0157, wondering if my o2 sensor is just no good 🤔