Active Autowerke High Flow Cats with borla x pipe

[qubaldo]

Like the title says, can i do that? I just bought my m3 and it has the testpipe and borla x pipe with cnt exhaust. Obviously I have the CEL on. Since the car still has warranty I would like to remove that CEL. The question is can i pair the high flow cats with the borla x pipe and remove the CEL in the car..?

This is what i was planning on buying if i can do that :

https://thmotorsports.com/i-1977476....ci0hoCQbfw_wcB

[SYT_Shadow]

There seem to be zero success cases of aftermarket X pipes with HFC not causing a CEL without a tune.

I think you will need a tune

[chillp]

I've been running the full ESS exhaust with HFCs for over two years and no CEL. I used the system for over a year without the ESS tune (so that's not the reason for not getting a CEL). Good luck!

[STR8-6IX]

Originally Posted by chillp

I've been running the full ESS exhaust with HFCs for over two years and no CEL. I used the system for over a year without the ESS tune (so that's not the reason for not getting a CEL). Good luck!

is the test pipe a primary or secondary cat delete?

messing with your exhaust PAST the primary cats and o2 sensors will not yield a CEL, and you dont need an ECU tune.

eg. deleting your secondary cats = no CEL. the ECU will adjust to the mod within 350 miles on its own. no tune needed.

[chillp]

Originally Posted by STR8-6IX

is the test pipe a primary or secondary cat delete?

messing with your exhaust PAST the primary cats and o2 sensors will not yield a CEL, and you dont need an ECU tune.

eg. deleting your secondary cats = no CEL. the ECU will adjust to the mod within 350 miles on its own. no tune needed.

The full ESS system replaces the stock x-pipe with one that has HFCs (in place of the more restrictive cats), no secondary cats, and two resonators (you have the option of choosing an x-pipe with 4 resonators instead of the HFCs, but that's not my setup and that will certainly throw a CEL). Some have said that the HFCs will eventually throw a CEL, but that hasn't happened yet with my ESS system.