kcmiddle

i have a 2000 silverado 1500 with a 5.3l 4x4 i have a P0430 Catalyst System Low Efficiency Bank 2 code and i am not able to pass emissions in washington state i have replaced the downstream o2 on the right side and now have replaced my cats with Walker Direct Fit Catalytic Converter from summit racing and i am still having this issue any help would be greatly appriciated i have done all the work myself and am lost the only other thing i can think of is the upstream on bank 2 is bad as well any help would be greatly appriciated as i am running out of options myself.

kcmiddle

my truck has 141k on it any ideas?

Suburbazine

Tune it out?

kcmiddle

if i tune it out will it be able to pass emissions? wont they be able to tell when they plug in the OBDii?

greasemykey

iTrader: (5)

it is the upstream O2 sensor that is your problem.

kcmiddle

everything i have read and the mechanic i talked to all pointed to the downstream and cats any info you have that would make the upstream the culprit would be appriciated

livefast1

iTrader: (1)

I dont think the upstream has anything to do with the catalyst monitoring system. The back o2 sensor looks for a flat signal unlike the upstream sensor which is constantly switching from high to low. If you monitor the downstream sensors and they have a switchrate similair to the fronts, the cats are usually burnt out.

kcmiddle

i didnt think the upstreams had anything to do with it either but i am open to any ideas its atleast worth it to test it and make sure its ok but i have replaced the cats and the passenger down stream and still no luck

livefast1

iTrader: (1)

Switch the passenger downstream you replaced with the driver side, clear the code and make sure you didnt get a bad sensor.

kcmiddle

ill try that next thanks