New exhaust cat delete???

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iamdub

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What is a "spark plug non-fouler trick"?

joe

You buy these:

81eJ5crhFRL._SX425_.jpg



And screw one into the other. Then you unscrew the O2 sensor, screw the stacked non-foulers into the O2 sensor bung, then screw the O2 sensor into the non-fouler. They space the sensor out of the exhaust stream so it sees less of the emissions and reports that all is well. Each non-fouler has a small hole in it, so you drill out the one that the O2 sensor will go into (the "top" one) and leave the one that goes into the exhaust pipe (the "bottom" one) alone. If it still throws a code for not enough emissions (whatever the technical term is for that), then the sensor is not seeing enough emissions. You drill out the hole in the bottom one a little and run it again. It may work the first time around or you may have to open the hole a few steps larger. Overall, it's not a whole lot of work and a $5 solution to avoid a few hundred bucks in cat converter replacement. They have different sizes of non-foulers, so you'd just need one that has the same thread as your O2 sensor.


foulers0005.jpg


image012.jpg
 

homesick

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You buy these:

81eJ5crhFRL._SX425_.jpg



And screw one into the other. Then you unscrew the O2 sensor, screw the stacked non-foulers into the O2 sensor bung, then screw the O2 sensor into the non-fouler. They space the sensor out of the exhaust stream so it sees less of the emissions and reports that all is well. Each non-fouler has a small hole in it, so you drill out the one that the O2 sensor will go into (the "top" one) and leave the one that goes into the exhaust pipe (the "bottom" one) alone. If it still throws a code for not enough emissions (whatever the technical term is for that), then the sensor is not seeing enough emissions. You drill out the hole in the bottom one a little and run it again. It may work the first time around or you may have to open the hole a few steps larger. Overall, it's not a whole lot of work and a $5 solution to avoid a few hundred bucks in cat converter replacement. They have different sizes of non-foulers, so you'd just need one that has the same thread as your O2 sensor.

LOL those look like the non-foulers from '70s JC Whitney catalogs.

Thank you sir.

joe

foulers0005.jpg


image012.jpg
 

drakon543

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those or angled ones depending on your need. they have longer ones than the one in the picture so you dont have to stack them or ones with a 90° angle.
 

nath

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I like this thread. Does anyone know how much difference it makes running no cats verses a "high flow" cat such as the stainless Y pipe and high flow cat from Magna Flow. I installed this set up on my rig about 7 or 8 years ago. Been working great ever since then. I think it was about $350 back then. But didn't notice much difference over the worn out stock set up. But the truck did have 225K miles back then...
Hey man I had mine removed for test pipe and got an MPG increase of 2 mpg, just saying temporarily of course (2 years later).
 

Javie

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Whoever previously owned my tahoe bought the cheapest duel exhause they could and now its all rusted out.
I want to go new from the headers back. Since i have passed emissions for the last time (washington state no longer doing emissions... supposedly) i was thinking of skipping the cats.
Has anyone done this? Im wondering if the 02 sensor after the cats is going to throw a code
I deleted both cats in my 02 tahoe and it was throwing a code i believe po420? Just went and had it re tuned to run without the cats. No more codes
 

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