[BGut12]

So I’m running VRSF catless downpipes, chargepipe, BMS intakes and have a muffler delete. For this situation only the catless downpipes matter.

Everyone who uses MHD is going to know about everything i’m about to say but I need to get specific. For emissions to pass me in Illinois, the “Catalyst” needs to read as complete, not “not available.” I went last week when it said not available trying to test it out (since i’ve found others say they’ve passed when it says not ready) and the guy immediately told me it failed because it didn’t read my cats.

I finally found a solution that partially worked. A lot of people say to check mark the box “OEM catted downpipes” so I did that so the tune can actually read the cats. I drove around for about 50 miles normally, babying it not anything crazy, and sure enough, catalyst say “Complete” but not without a catch. I get the DME code for “catalyst efficiency below threshold/limit.” The problem is with this code popping up, my CEL also pops up… Now if I click on “Delete DME codes” on MHD, it doesn’t just clear the efficiency code, it resets the entire readiness of the car, so EVERYTHING goes back to INCOMPLETE or not available and I have to do a drive cycle again.. it’s an endless circle. If I toss on the “OEM catted downpipes” option, I get the efficiency code. If I don’t, the catalyst comes up as not available and won’t pass emissions either. The only thing I still have to try is I believe there’s a 5-10 mile sweet spot where the catalyst will say complete but my CEL won’t pop up on the dash. But even if that’s true the code for efficiency still exists in the DME codes so would the tester stop it from passing?

What in gods name do I have to do? It seems there is no workaround with MHD without a DP fix and all that.

Keep in mind i’m still trying to run the car on MHD’s stage 2 tune. People say to go back to stock tune and check mark the “OEM catted downpipes” option. In reality none of that matters because it will still throw 1. catalyst efficiency the same way and 2. car is running rich. I’ve tried going back to stock tune like others and it just throws the CEL and even more DME codes than being on stage 2.

[Tkenupp]

Originally Posted by BGut12

So I’m running VRSF catless downpipes, chargepipe, BMS intakes and have a muffler delete. For this situation only the catless downpipes matter.

Everyone who uses MHD is going to know about everything i’m about to say but I need to get specific. For emissions to pass me in Illinois, the “Catalyst” needs to read as complete, not “not available.” I went last week when it said not available trying to test it out (since i’ve found others say they’ve passed when it says not ready) and the guy immediately told me it failed because it didn’t read my cats.

I finally found a solution that partially worked. A lot of people say to check mark the box “OEM catted downpipes” so I did that so the tune can actually read the cats. I drove around for about 50 miles normally, babying it not anything crazy, and sure enough, catalyst say “Complete” but not without a catch. I get the DME code for “catalyst efficiency below threshold/limit.” The problem is with this code popping up, my CEL also pops up… Now if I click on “Delete DME codes” on MHD, it doesn’t just clear the efficiency code, it resets the entire readiness of the car, so EVERYTHING goes back to INCOMPLETE or not available and I have to do a drive cycle again.. it’s an endless circle. If I toss on the “OEM catted downpipes” option, I get the efficiency code. If I don’t, the catalyst comes up as not available and won’t pass emissions either. The only thing I still have to try is I believe there’s a 5-10 mile sweet spot where the catalyst will say complete but my CEL won’t pop up on the dash. But even if that’s true the code for efficiency still exists in the DME codes so would the tester stop it from passing?

What in gods name do I have to do? It seems there is no workaround with MHD without a DP fix and all that.

Keep in mind i’m still trying to run the car on MHD’s stage 2 tune. People say to go back to stock tune and check mark the “OEM catted downpipes” option. In reality none of that matters because it will still throw 1. catalyst efficiency the same way and 2. car is running rich. I’ve tried going back to stock tune like others and it just throws the CEL and even more DME codes than being on stage 2.

hi there! I'm coming from the 350z world, just got my n55 e92 and i hope i can contribute to this community also. On the vq community we used to put a spacer between the downstream o2 sensor and test pipes, that will work as a mini cat. there's also a piggyback device that you can install. Those devices are intended to keep your emissions monitors complete during trackdays and off road use only, not legal for street use tho.

https://www.magnumtuning.com/en/deta...ect-box-anchor

[BGut12]

Originally Posted by Tkenupp

hi there! I'm coming from the 350z world, just got my n55 e92 and i hope i can contribute to this community also. On the vq community we used to put a spacer between the downstream o2 sensor and test pipes, that will work as a mini cat. there's also a piggyback device that you can install. Those devices are intended to keep your emissions monitors complete during trackdays and off road use only, not legal for street use tho.

https://www.magnumtuning.com/en/deta...ect-box-anchor

appreciate this bro, might have to try it thank you! hope you enjoy the car, its extremely fun to drive and mod