Does the error codes caused by High flow cats cause your ECU to detune your engine performance?

I recently got the p0420 catalyst system efficieny below threshold bank 1 and p0430 catalyst system efficieny below threshold bank 2.

I used Cipher to clear it. But curious if performance would have been affect had I not cleared it???

 

I have the same problem and i believe there wont be anything wrong with performance.

 

nope.

 

No. You can buy non-foulers to clear the issue perm. if you don't like CELs. Its only 20-40 bucks and an easy install.