I installed invidia gemini cat back along with 60mm invidia test pipes.

After driving the car a few hours my service engine soon light came on, I scanned and i got the codes p0420/p0430 cat inefficiency bank 1/2.

Im assuming this is because of the test pipe install. Do i need 'defoulers' to clear this code?
If so can someone tell me what ones i need to buy?

 

You need a tune to make the car actually run right. The ECU is expecting it to have cats and now it doesn't... not going to run right.

 

Can I not just get 'defoulers' to solve the problem?

Do the downstream 02 sensors affect performance?

 

The defoulers trick the O2 sensors into giving a false reading so they don't throw a check engine light, but since the ecu is still expecting the cats to be there the air/fuel ratio will be way off. Only way to correct it is with a tune

 

Yeah im going to go get the up rev tune here once i finish installing my plenum.

Im going to swap out the test pipes with some hfc as well. its way too loud for my taste.

 

i have the same problem, only that i have megan HFC's. With the defoulers i still had a PA203 code, and without them i have these ones too, what options do we have for tuning?

 

Uprev Osiris is pretty much the only game in town for NA tuning, good thing though its amazing