MiketheCalamity

So I was talking to a mechanic about installing my Kooks headers and cat'd xpipe and he told me that the post cat O2 sensors may make the check engine light go on and cause problems with the state inspection. I wanted to know if anyone had any information on this. Also I read a little snip that the Diablosport Predator can fix this problem, how true is that and how would I do that?

Str8pipe03GT

I'm not sure about the heades and X pipe you have, but I do have a Diablo Predator. You can fix this problem and it is quit easy. Depending on what model tuner you have, you can disable the rear O2 sensors and clear the code if you have had a MIL come on. I installed a catted X pipe from BBK and have not had any problems with the MIL yet...You can tell that it is def running a little richer, but not enough to trip the sensors. If you do need to clear the code when the MIL pops up, you can connect the Diablo Predator to the OBD port and follow the start up. It will then give you some options, such as tune, custom tune, and diagnostics. If you click the diagnostics, it will then give you the option to see the code and then CLEAR the code, with no "footprint" when going to emissions. I have personally had the light pop up in the past and cleared it and when going to emissions, they CAN NOT tell you cleared it. Hope this helps!

Bobby

2007VistaBlueGT

Any tuner can bypass the MIL for rear o2's if the person making the tune has any idea what they're doing.

SirKnightTG

Hmm, I wonder if the SCT clears the codes in the same way by not leaving a footprint. I didn't know that was possible.

Str8pipe03GT

I'm not sure about the SCT, but the Diablo WILL NOT leave a print

stang910

If you disable the rear O2's and have OBDII state inspections you won't pass. The rear O2's must be turned on the pass an OBDII inspection. To help answer your question I have the kooks longtubes with catted X pipe and they don't throw a CEL. So from my experience with them your gonna be fine.

SirKnightTG

Good to know if I ever have to do emissions one day.

mikez

i have the kooks with catted x-pipe with all 4 O2 turned on and have never thrown a code, still passes just fine

nmd55

i have kooks and catted x-pipe with all 02 sensors on too, and have yet to throw a code. but like some else said you can tell its running a bit rich.

zkiller

I had to have my O2 heater circuit adjusted in tune to get rid of the DTC from my 1.75" Kooks.