Engine Light On Code Po430

I have a 2000 LS V6 w/ sport pkg....it currently has 86000 miles on it. I love the car but things are really starting to go wrong...I just replaced 4 engine coils, alternator, and brakes in the past 2 months. Now the engine light is on again. I brought it to Auto Zone and had the codes read. It said PO430 "The catalyst system efficiency for bank 2 is below threshold for the current engine operating conditions". I think it may be the mass air flow sensor because the one in there looks really cheap and aftermarket. Any suggestions would be greatly appreciated. I just dont have the funds to bring it to the dealer right now. Thanks!~

I would not expect the MAF to effect only one cylinder bank. That is, assuming that a similar code for bank 1 is not soon to follow.

Does the car seem to run fine and have normal power?

Which coil packs were replaced (cylinder numbers - ie: Were 3 of the 4 on bank 2)? Did you clear the codes using a scan tool after replacing the coils (disconnecting the battery is not sufficient).

If you private message me with an e-mail address for you that can accept PDF attachments, I can send you the troubleshooting steps for code P0430 for a 2002 LS.

-Rod