Originally Posted by gkos_

-.- gf can't translate Haha
Umm how are the o2 sensors triggered

Originally Posted by BrowningSCrew

I couldnt seem to find any threads about this mod, so I'm making one myself.
What does this mod do? this mod tricks your O2 sensors into thinking that your catalytic converters are still there so you do not throw a code when you cut them off.
How does it work? the spark plug non-foulers restrict the flow of gasses getting to the sensor therefore making it think the cats are still there filtering

Supplies needed-
[*]2 sets of 2 18mm spark plug non-foulers part number 42009[*]PB Blaster or some other rust penetrant[*]1/2" drill bit and a drill[*]19mm wrench[*]a set of channel locks[*]ratchet with an 8mm socket[*]a very small flathead screw driver
to start out, unhook the negative battery cable using your 8mm socket

now get under the truck and spray the living crap(for lack of a better phrase) out of the o2 sensors with your penetrating spray

while the PB is doing it's job go get your spark plug non foulers

and drill a 1/2" hole in the end of two of them. Careful not to booger your threads. This hole allows the top one to screw over the tip of the sensor shown here

After you have your holes drilled go inplug the sensors, use the little screw driver to pop the prong on the plug and relese it.

Unscrew the sensors from the pipe and take them out.

put the drilled out fouler onto the sensor first, tighten it down, then put a non drilled one over it and tightnem it down as well. it will look like this before you put it back in

Now screw it back into the pipe, tighten it up, then plug it back in

All thats left to do after that is hooking the battery back up.

Before I did this my CEL was on, when I started it up after this it promptly went off. As usual, if You have any questions I am happy to help

Originally Posted by Bill's03F-150

What size pipe did u put in place of the cats?

Originally Posted by BrowningSCrew

Same as the rest, 2.5 I think. Just flared at the ends to slip over the pipe at each end.

Originally Posted by Bill's03F-150

I don't have to worry about an elbow do I? Are both sides straight?

Originally Posted by BrowningSCrew

Hahaha ok, to the best of my understanding they read the gasses coming through the exhaust to measure o2 output and adjust the engine parameters accordingly. When you cut the cats off it lessens the restriction of the exhaust, but it also lets more o2 gasses pass, which the sensor reads as a bad thing and triggers the check engine light. This mod restricts the gasses to the sensor and makes it think the cats are still there working. If that answers your question?

Originally Posted by 7700SCREW

How your o2 sensors work is the 2 closets to the engine (should never be messed with) provide the engines computer with the data it needs to make your engine run as efficiently as possible.

The rear 2 are just for emissions and are not needed to make the engine run.
By doing this you reduce the amount of exhaust that passes by them reducing the chance for a check engine light.

Originally Posted by TheKing1985

What states require emission testings? We don't have any in Minnesota ...as far as I know.

Originally Posted by BrowningSCrew

I'm not sure what states do.