CATS cleaned out, error codes and terrible sound
Anybody had all four removed or "cleaned out"?? How did it sound or effect performance/economy?
I do have an O2 sensor bypass after the first CATS and don't have any error codes for sensors.
I do have several error codes that have appeared and changed #'s on me.
There's a little wrench and the error codes proceeding 600, then changed to 500 and then 400 and has only displayed the little tool and 400 for past several weeks.
Please advise.


