How important are catalytic converters?

I bought a 2000 Tacoma 3.4L / V6 four months ago that is missing both of its catalytic converters. I’m just wondering, aside from being environmentally responsible, how important are catalytic converters?

In my experience of previously owning a 1995 Corolla DX wagon, I know that Toyota builds their vehicles pretty tight, where you definitely want to get the most out of your compression. Do missing catalytic converters affect compression?

Yes, I’ve already observed a false code being thrown in their absence (with the “check engine” light coming on) — but I’ve already found a workaround for this. All I have to do is engage the extra power [ECT] mode & put my foot in the pedal for a little bit; and the check engine light goes off. -lol-

Your experience & expertise is appreciated. Thank you in advance.

 

The emissions on the older Toyota trucks isn't like todayss emmisionsIt . You can get away with buying a cheaper converter. I just replace mine for 199 bucks off eday all codes went away.

I only run 1 converter and a resonator

 

On my race/street car(when I was younger) I ditched my cat
I couldn’t handle the smell
Then, discovered that reputable tuning shops wouldn’t touch a car with license plates without cat(s)

there are cheap ones out there
https://www.summitracing.com/parts/...MI18bK5uvMggMVAZxaBR2juQjPEAQYASABEgLQgfD_BwE

 

depends if you need a DEQ check for tags
and how the engine management computer is being tricked into not seeing the results it expects to see (sounds like this is becoming a problem)

 

Nah … my area doesn’t require emissions testing. It’s also my understanding that a lot of areas that DO have emissions testing have a “grandfather clause” for older vehicles. (Whether a 2000 fits within this clause or not, I do not know).

The rampant theft of catalytic converters is the biggest problem. And I wouldn’t doubt that the guy who sold me my truck yanked them himself. (He was kinda’ shady). The windshield washer reservoir & pump was also missing at the time of purchase; and I just didn’t observe its absence at all. :-|

With that said, I’m still super pleased with my Taco!!

 

Gasoline engines ran for almost 75 years without catalytic converters. They are there only for emissions.

 

Put some aftermarket cats on it...nobody will steal those as they have no scrap value.

There's really no reason not to use them, they are not a restriction like the units from the '70s. After having been around vehicles that run right and burn clean, I can't stand the smell of a vehicle running with no cats....they stink.

Also, not sure WTF you're talking about with being tight and getting the most out of your compression lol...Learn how engines work and revisit that. The code is not "false"....the system is designed to detect emissions system faults, and missing catalysts is an emissions system fault.

 

They don't do anything but choke the exhaust flow. If you have a CEL, do what the turbo guys do and run an O2 spacer.

The guys complaining about the smell drive slow vehicles

 

Engines that have cats were designed to have some back pressure on the exhaust line. I wouldn't be eliminating that without knowing how to rework the manifold.

 

They don’t choke shit. Lol. You can see through them. Production cars make north of 600hp with cats….cats are not robbing horsepower from a Tacoma engine.

 

This isn't 1492, backpressure doesn't apply here.

 

If you can see things in a pipe, then it's a choke point.
Remove those cat(s) from the production 600hp cars and you'll make more power, because they're choke points. Don't get mad, that's just the way it is.

 

The colder the gases that go in the cylinder...the greater the efficiency.

The cat actually counters this....makes the cylinders run hotter.


However it is illegal to run a factory cat car without the cat in the US...

although, there are no cat police patrolling the highways....


Without the cat you'll get all kinds of weird codes...

 

I'm running no cats with a urd Sim without codes. Only time when I get a p0420 is when I offroad. Other than that, while in town driving, my mil light is off and nothing soft store.

 

Cats are restriction.... sadly, that's the truth even though you're able to see some form of light through them.

 

By that logic, your truck would make more power without the air filter in place....but it doesn't.

You'll likely notice that the body of the cat, where the substrate exists, is significantly larger than the rest of the exhaust pipe. The amount of clear path through a modern cat is the same or greater than the amount of clear path through the empty pipe. We're not dealing with old domestic cats here that are full of beads...

Things are sized appropriately to work correctly. The reason performance / race shit doesn have cats is not because they make more power without the restriction, it's because the tune / design would burn down the cats....and they're such limited use vehicles that nobody cares and they have better things to spend their money on.

 

Whether they’re restrictive/choking points or not, would we really even notice a difference in performance if one were to remove them? With these engines? Idk man. Someone should dyno test this theory.

 

no, you wouldn't notice a difference.

 

You can read a book looking through a modern catalytic convertic...it's a bit better than "some form of light".

 

If that cat is clogged from excessive oil burn on an old engine...
removing it would give significant improvement...

especially under load.....

one of my bosses high milage F150's was like this.... gutless under acceleration...