P0420 CODE AFTER INSTALLING KOOKS HEADERS AND GREEN CATTED X PIPE.....HELP!!

[Neil1b]

I have been using one of the big companies mail order tunes since i started modding due to their reputation.........everything was going great with tune revisions etc.

Until...............

I added kooks headers and the green high flow catted x pipe.

Now i am getting th p0420 code.......

So i did some research and found that the rear o2's need to be removed or adjusted in the tune.

Soni contact the "big" company and they basically tell me to beat feet........they cant help me with the code nor unlock the tune so that someone else can...........so i wasted ove $600 bucks on a mail order shit tune whenni could have had a locally dyno tune.

Any suggestions?

I feel that this company should do something rather that have me fail emissions now that a checknengine light is on even though i have cats.

 

[HillbillyHotRod]

If you are looking to disable the rear sensors none of the tuners will do that. Big time fine to do so.

 

[Neil1b]

So what are thr options???? I know im not the only one

 

[merkyworks]

As other have and will tell you, no big company is going to mess with turning off the rear O2's (basically turning off part of emissions controls). After recent EPA blah blah blah lawsuit/fines against SCT parent company people aren't messing around anymore.

Did you use O2 extender harnesses? If so this could be your issue.

 

[Cobrakit]

I installed o2 extenders (not harness) on rear sensors and it seemed to work. This pulls the rear o2 sensors out of the flow somewhat. Did this because of supercharger not long tube headers. Sold car so i don't know hoe long it worked. OBTW same comment about tuners. Device manufacturers got in trouble recently with the government!

 

[Catmonkey]

My understanding is that it is a felony to deactivate the rear O2 sensors. Tuners don't want to go to jail. A felony conviction tends to take away quite a few of your personal freedoms. Not that I know about such things.

 

[sleek98]

Recently purchased hp tuners and have been doing my own thing for a couple months now so i haven’t really thought about it, as Lund turned it off but that was 3 years ago. I know vmp won’t anymore and bj has said he won’t. But I haven’t heard anything about PBD or Lund.

I would try anti foulers first to see if it pulls it far enough out of the flow so it doesn’t set the light off. That would be the easiest and cheapest route to try first.

 

[RedVenom48]

I have been using one of the big companies mail order tunes since i started modding due to their reputation.........everything was going great with tune revisions etc.

Until...............

I added kooks headers and the green high flow catted x pipe.

Now i am getting th p0420 code.......

So i did some research and found that the rear o2's need to be removed or adjusted in the tune.

Soni contact the "big" company and they basically tell me to beat feet........they cant help me with the code nor unlock the tune so that someone else can...........so i wasted ove $600 bucks on a mail order shit tune whenni could have had a locally dyno tune.

Any suggestions?

I feel that this company should do something rather that have me fail emissions now that a checknengine light is on even though i have cats.

Its the brave new world. We speed enthusiasts had a good run from 2003 to 2018, but the goose is cooked. As others have mentioned for a registered street going vehicle, none of the tuning companies will turn off rear O2 check lights.

Ill have to look at anti foulers as well for track days with an off road H. I need my check light to tell me if something has gone wrong. A Check light staying on is not an option.

 

[MelloStang2010]

Just get some spark plug non foulers as mentioned above. I ran them on my old coyote because I was getting the p0420 code even with cats, once they were on no more CEL. Did the same thing with my gt500, longtubes, no cats, and no check engine light. I was able to pass emissions as well using the non foulers and Im currently tuned by lund who will not turn off the rear sensors.

 

[Neil1b]

Awesome.....just ordered pair from big daddies