p0420 with rear o2s and high flow cats

[[email protected]]

have an 07 z06 with full LG longtubes and their high flow cats. here in phx, our emissions test is pure plug in and check for readiness, nothing else. but the car is getting 420 code.
disabling the code in dtc section will just stop the code and it will never go ready - correct? same for disabling the test itself in general?
with my uprev nissan software, i can alter the acceptable range for the rear o2's to make this work, but there isn't anything like this in the software (that i can find).
how to do this properly - ie, readiness is set?
searches do not get specific advice, only generalizations.
thanks in advance.
tk

[DSteck]

Legally, nobody here can answer your question. Haha.

I'll leave you with this: 3

[[email protected]]

that's what PMs are for!
but i think i get it, and sure you can. forums are the place where people discuss this. if the govt was truly serious about things, we'd have no car culture. it would be like italy and france where modifying even your wheels is not allowed (no larger than stock).
anyone else - don't be afraid.

[killian322]

Hello,
I have an 07 Impala S and sincew I have had the exhaust changed, I am getting the same code and I have been told by many the way to fix this is to go to your local auto parts store and purchase spark plug non foulers and install them in between your O2 and the Cat, this will alleviate the code for you.This is what I have done and so far it works.


tony

[drayrunner]

I have never heard of that fix, and you say it really works, hard to beleive, do you have any idea why it works, I would like to know that if possible, the reason i'm posting, i have a problem with my cat light staying on.

[DSteck]

that's what PMs are for!
but i think i get it, and sure you can. forums are the place where people discuss this. if the govt was truly serious about things, we'd have no car culture. it would be like italy and france where modifying even your wheels is not allowed (no larger than stock).
anyone else - don't be afraid.

HPT doesn't want people saying it.

[Mike@G-Force]

Saying what?

[[email protected]]

that works quite a bit and is usually your cheapest way out. half the time on cars that don't even have cats, that will work.
but when you have the ability to edit the ecu directly, one shouldn't have to resort to hardware fixes. that's why i did this post.
but dsteck is correct. i set to 3 and the ecu ran its tests and had full readiness. emissions check complete.

[DSteck]

Saying what?

Saying how to beat emissions tests.

[BERSERK]

have an 07 z06 with full LG longtubes and their high flow cats. here in phx, our emissions test is pure plug in and check for readiness, nothing else. but the car is getting 420 code.
disabling the code in dtc section will just stop the code and it will never go ready - correct? same for disabling the test itself in general?
with my uprev nissan software, i can alter the acceptable range for the rear o2's to make this work, but there isn't anything like this in the software (that i can find).
how to do this properly - ie, readiness is set?
searches do not get specific advice, only generalizations.
thanks in advance.
tk

what mods do you have?

[killian322]

Just wanted to let you all know that I installed the spark plug non-foulers on my 07 Impala SS and so far I have not gotten the P0420 code any longer. This really does work.