removing catalytic converter

i have a 96 tacoma 2.4l engine. i want to remove the catalytic converter and replace it with just a straight pipe directly into the muffler. ive done this once before with a hardbody nissan. can it be done with a first gen tacoma?

 

Not a good idea. The truck won't ever run right.

Replace the cat with quality aftermarket unit for best results.

 

Just curious, why it will not run? To my understanding first O2 sensor (before cat) is used to tune up the fuel/air mixture, the second O2 sensor (behind cat) is used for emission check only. Replacing cat with pipe will screw up emission check and will throw the engine check light (and will not pass emission obviously) but should not affect driving. I have not done it yet, but I read that there is some RC filter O2 sensor mod that would fool the ECM to not throw engine check light.

 

My brother tundra has no cat and it does not run right at idle due to it. Unless you re program the computer it’s always gonna throw a bad fuel to air

 

uhm, it will run fine, just need to get a Rear o2 simulator

https://www.urdusa.com/urd-rear-o2-simulator-5vz-fe-3-4l-v6/

 

It will run but throw a CEL light. If you live in a place where they have testing (Which you must not have) it will be fine. You can also buy an 02 sensor elbow to trick it into thinking there is gas pressure in there and it will not affect the 02 sensor. It will stink, it will be loud. Do what you want. It's bad for the environment but hell - so are people in general. lol

there is that rear 02 simulator mod that is quite inexpensive as well. Lots of people on here do it. Ever priced an OEM cat? Holy ---- You can also get an aftermarket cat. Your engine will be happier with the cat - however since they are designed for the back-pressure.

 

Please explain..

Why would his engine be "Happier" that a restriction is there?

 

Because they engineered the engine with the back-pressure from the Catalytic converter in there. I am just assuming that the ECM,Fuel to air ratio, MAF sensor all play a part in that. Beside pollution control it's beneficial in my opinion.

Someone would have to do a dyno test on the 4 banger or 6 to show any real data on that though. Maybe on a big V8 or something that displaces more would more exhaust flow benefit anything. I think most people do it because the cat is clogged and getting rid of it for a straight pipe is a cheap alternative.

 

I have this on mine. Put straight pipe in after my converter was stolen. Works great to eliminate the check engine light and I have no drive-ability issues. If I were in need of replacing the entire exhaust I would probably start with a new converter just because of the environmental thing.

 

Don’t do that.

Cut it off after the cat, or replace the cat with a more free-flowing one.

 

Bartmaster1234 do you have a particular reason as to why i shouldnt cut the cat off?

 

Like said above, The engine isn’t designed to deal with that lack of back pressure from the cat. You can run an O2 simulator if you want to rid the CEL.

I read a post on this forum of someone who cut it off at the headers. He said his truck sounded like an “angry bumblebee”.

Why do you want to straightpipe it, the sound?

 

From my experience, sawzalls are quick and easy, take cats out in a jiffy

 

I’m calling PETA

 

I’m just saying, thousands of cats have been cut out with a sawzall

 

1) All the cool kids are freaked over climate change. Whether you buy that or not, there is nothing redeeming in ICE emissions (of all kinds of things). Don't be part of the problem.

2) it's actually Federally illegal, even in non emissions states. And a random roadside inspection can cause you grief.

3) if you are off-road only (as in tow it or live on your own land and never leave), as in not plated, registered etc., you might be 'legal'. Doesn't mean that polluting is good.

4) there is nothing to gain from cat removal other than noise making. If you think the OE cat is restrictive, install a performance one. Don't believe me, prove it out on a dyno. Not a butt meter, a real one.

 

Agreed. If you’re seeking sound, the exhaust without a cat won’t sound very good. A proper less restrictive car and even a better muffler would be much better.

 

Just go electric. Save the planet mofo! One Taco owner at a time

If I was you - to avoid too much grief and also remember you will smell like your exhaust. Everywhere you go. Your clothes - everything in there will smell like it. If - it's far enough away you won't but in traffic you are gonna stink. My local exhaust pros shop does a real kick ass deal on aftermarket catalytic converters. Quoted me about $145 to replace mine (total). That's a pretty sweet deal when compared to OEM stuff.

 

If you are seeking sound why not buy a good stereo and blast those decibels inside the cabin only. Why everybody else has to suffer from the noise form your truck?

If you want to get rid of the cat because you are afraid it will be stolen (or was stolen already), you can do what I did, when my OEM cat was stolen: put a new cat and some kind of theft protection. I went for "cat skid plate" solution. it is thick still plate bolted to the frame with secured bolts and blocking the cat from being cut or removed.



The same kind of protection I did for my 2012 4Runner as soon as I got it home. 4Runner has 2 converters on both sides of transmission, so I adopted OR-FAB skid plate designed for 3-rd gen Tacoma.



Simple solution - if you can't see it, you can't steal it.

 

Those are all good ideas. I've never heard of that being a problem where I live and I assume that those plates are not very cheap. My dog usually hears anybody remotely close to the house. They wouldn't stand a chance. lol