02 impala displays code 0420,catalytic below efficency, component $60, bank 1 -8122 should be {8000 just had original catalytic replaced (obstructed) 500 miles ago , what is Bank 1? ?????????
vf171
6/4/2007 7:11:15 PM
Bank 1 should be a general position locator if I remember correctly. On my '99 Silverado I was getting similar warnings, only mine would say something like "Bank 1, Sensor 2". I think Bank 1 meant left or right side (exhaust manifold) and Sensor 2 meant post-catalytic converter. I had 4 O2 sensors total IIRC.
Good luck.
