andrew29620

Hey guys I have a 06 fx4. Im wanting to straight pipe my truck. I'm wanting to remove the two big cats that are by the transmission. Heres mh question. If I get my 02 sensors put back in my pipe will my check engine light come on? Ive heard yes and no. I will get the 02 sensors put back but wanting to know about the check engine light.

Mdgonzo101

The primary O2 sensors MUST be in place in order for the truck to operate correctly. You can fool the rears into thinking the catalytic converters are there by using spark plug non-foulers. Get 4 of the 18mm non foulers. Drill out 2 of them with a 1/2" drill bit. Screw in the rear O2 sensors into those modified non foulers. Then mount the modified non foulers into the unmodified non foulers. That whole assembly goes into the rear O2 bung.

So the order goes this way: Rear O2 bung -> unmodified non fouler -> modified non fouler -> rear O2 sensor.

andrew29620

Thanks man. I will have to try it. Might go ahead and buy new o2 sensor and fix it up for when I get it straight piped. My exhaust guy said he can put my o2 sensors back in my pipe. So the recreated o2 sensor will just scRew directly into the pipe?

Mdgonzo101

It should so long as they use the correct bung.