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I am going to delete both catalytic converters on my 2001 Tundra but I am not sure what to do with the O2 sensors.

How do I keep the check engine light from coming on?

Can someone show me a step-by-step demonstration?

I don't know anything about wiring diagrams but I can learn.

Thanks.
 

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Is there a reason you are deleting them?
The check engine light will come on. I believe the only way of preventing the CEL from coming on is by spending some $$$ on a sensor simulator. It's not a guarantee, though.
 

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How do I keep the check engine light from coming on?
You keep the check engine light from coming on by leaving the catalytic converters in place.

The ECU (Engine Control Unit) measures the rate of air flow into the engine via the MAF (Mass Air Flow) sensor. It injects fuel via the injectors at the proper rate to match the air flow rate. It senses the O2 level in the exhaust, both before and after the converters, to enable the ECU to act as a classic "closed loop control system" in which the drive to the injectors is continually calibrated. Without the O2 sensors, the ECU would have to act as an "open loop" system in which the injector drive is uncalibrated, and the fuel mixture would always be either too rich (which wastes fuel) or too lean (which damages engines). If the converter is not in place but the O2 sensors are, then the measurement of the O2 sensor that is normally after the converter will not be correct, the ECU will complain via the check engine light, and likely your engine will run like crap.

So, why would you remove your converters?
 

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Hollowing out the converters does the same thing as removing them. It'll turn the check engine light on.
There are metals like palladium and rhodium in a ceramic honeycomb grid inside the converter. The harmful gasses enter the converter from the engine, are heated up, and are changed to mostly Nitrogen, Carbon Dioxide, and water. If you hollow out the converter, this chemical reaction won't take place and your post-cat 02 sensor will send data to the pcm which will turn the check engine light on.
 

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To the OP,

Is yours a V8?

I asked the same question a while back for my 2002 California compliant V6 (that was bought in Texas). Mine has 2 cats but they are inline and on a single exhaust pipe.

I never did get around to playing around with it by making a test pipe; yet.

The non Cali compliant of the same year were "rated" at 5 more HP, LOL, and I don't recall if there was a mpg rating difference also.
 

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Have you guys read the thread on here somewhere of a guy that did a DIY job of cleaning his cat/s?

He was getting the dreaded CEL codes from the old cats, and he used an old washing machine to heat water along with some kinda acid solution; mild I believe. He had a drastic improvement in power and mpg and didn't have to replace anything.
 

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I am going to delete both catalytic converters on my 2001 Tundra but I am not sure what to do with the O2 sensors.

How do I keep the check engine light from coming on?

Can someone show me a step-by-step demonstration?

I don't know anything about wiring diagrams but I can learn.

Thanks.
This is an unbelievably horrible idea and probably the result of misguided advice from someone who does not own a Tundra. Long story short you will never be able to keep the CEL from tripping. As DJ pointed out you need the functioning rear O2 sensors and the catalytic converters for the truck to run correctly. I deleted my cats and am running rear sims. The truck runs like crap. It runs so bad that I wanted to sell it but since it does not have cats, runs like crap, and new cats from Toyota are $1,600 EACH I am stuck with trying to find replacement cats that will work with the Toyota set-up. And you cannot throw just any brand of catalytic converter under the truck and expect it to work - many brands fail within a few months and companies, despite their warranties, will not continue to send you replacement parts just so you can burn them up.

You will gain nothing by deleting the cats. No gain in horsepower, no gain in torque, and no gain in fuel economy.

You keep the check engine light from coming on by leaving the catalytic converters in place.

The ECU (Engine Control Unit) measures the rate of air flow into the engine via the MAF (Mass Air Flow) sensor. It injects fuel via the injectors at the proper rate to match the air flow rate. It senses the O2 level in the exhaust, both before and after the converters, to enable the ECU to act as a classic "closed loop control system" in which the drive to the injectors is continually calibrated. Without the O2 sensors, the ECU would have to act as an "open loop" system in which the injector drive is uncalibrated, and the fuel mixture would always be either too rich (which wastes fuel) or too lean (which damages engines). If the converter is not in place but the O2 sensors are, then the measurement of the O2 sensor that is normally after the converter will not be correct, the ECU will complain via the check engine light, and likely your engine will run like crap.

So, why would you remove your converters?
^^^^ This times eleventy-billion ^^^^

I will add that the front O2 sensors which control A/F mixture are calibrated against the rear O2 sensors multiple times per second. The rear O2 sensors must have the cats in order to function correctly.

Is there a reason you are deleting them?
The check engine light will come on. I believe the only way of preventing the CEL from coming on is by spending some $$$ on a sensor simulator. It's not a guarantee, though.
Sims will only work for awhile.
 
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