Tuning an ECU to not set CEL with HF Cats

[dogears]

So I want to add a full exhaust to my new 09 DCT sedan. Headers back. I want to retain the primary cats. I do not want to set a CEL nor cut the stock exhaust.

Wouldn't it be feasible to reprogram the ECU so that the parameters that trip the CEL are modified to "play nice" with the addition of high flow cats?

For those that are unaware, it has come out that the addition of HFC does set a CEL.

I am not interested in turning of the ECUs post cat 02 sensor monitoring. In NJ we have OBD testing and I do not want to have to R&R a ton of stuff to get the car to pass emissions.

Thanks!

[Omar@ActiveAutowerke]

Originally Posted by dogears

So I want to add a full exhaust to my new 09 DCT sedan. Headers back. I want to retain the primary cats. I do not want to set a CEL nor cut the stock exhaust. If you were to retain your primary factory cats you would not have a CEL issue. The factory design does not allow for a bolt on option that will connect to your primary cats and eliminate your secondary. This is why you would be required to cut and weld.

Wouldn't it be feasible to reprogram the ECU so that the parameters that trip the CEL are modified to "play nice" with the addition of high flow cats? This is something that is being looked into.

For those that are unaware, it has come out that the addition of HFC does set a CEL.

I am not interested in turning of the ECUs post cat 02 sensor monitoring. In NJ we have OBD testing and I do not want to have to R&R a ton of stuff to get the car to pass emissions. Honestly depending on the type of testing it may actually be easier to swap out the system to your factory setup if you want to go with a primary cat delete option or you can connect to you factory primary cat via cut/weld.


Thanks!

Dear Dogears,

Reply above in red.

[dogears]

Thanks Omar!

I don't want to cut and weld if possible.

I also do not want to have to send the ECU out for reflashing two times in order to get the car to pass. Once to re-enable the sensor and again to disable the sensor. In addition to reinstalling the factory exhaust and then putting the AA stuff back on.

The ideal would be a full replacement exhaust that doesn't trip the CEL so I can leave the emission monitoring on in the ECU.

I guess cutting and welding is a possibility, however I wouldn't use the beautifully crafted AA stuff if that is my option.


Thanks again!

Originally Posted by Active Autowerke

Dear Dogears,

Reply above in red.

[J08M3]

Originally Posted by dogears

Thanks Omar!

I don't want to cut and weld if possible.

I also do not want to have to send the ECU out for reflashing two times in order to get the car to pass. Once to re-enable the sensor and again to disable the sensor. In addition to reinstalling the factory exhaust and then putting the AA stuff back on.

The ideal would be a full replacement exhaust that doesn't trip the CEL so I can leave the emission monitoring on in the ECU.

I guess cutting and welding is a possibility, however I wouldn't use the beautifully crafted AA stuff if that is my option.


Thanks again!

I have the same issue...

I think my solution is going to be eliminating the secondary cats. That way I have OEM primaries, with no effect on O2 sensors. I won't need to mess with my ECU. OEM exhaust is already an X-pipe, and it already has resonators just like AA's does. This will be a small fraction of the price, should have no problems passing inspection, and according to a few companies there is only minimal gain at best by replacing OEM cat with HFC.