How The Most Hated Auto Part Changed The World

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According to the Environmental Protection Agency’s estimates, in 2019, 7% of the light-duty vehicles in the United States did not comply with their mandated vehicle emission regulations. Even more astonishing, is the fact that one specific component on these vehicles accounts for about 68% of these compliance failures.
HISTORY OF SMOG
Though the catalytic converter has become the primary mechanism of the automobile industry for controlling exhaust emissions in internal combustion engines, its origin is a byproduct of industrialization as a whole. During the turn of the 20th century, the smog created in urban areas by factory smokestacks triggered the first concerns for air quality. As the automobile and the internal combustion engine became more abundant, their impact on air quality grew more worrisome., During the 1940s, In the United States the growing problem of urban smog, specifically in the Los Angeles area prompted the French mechanical engineer Eugene Houdry, to take interest in the problem. Houdry was an expert in catalytic oil refining and had developed techniques for catalytically refining heavy liquid tars into aviation gasoline.
WHAT IS SMOG
The exhaust of all internal combustion engines used on vehicles is composed primarily of three constituent gases, nitrogen, carbon dioxide, and water vapor. In lean operating modes of gasoline engines and in diesel engines, oxygen is also present. Diesel engines by design generally operate with excess air, which always results in exhausted oxygen, especially at low engine loads.
The nitrogen and oxygen are primarily pass-throughs of atmospheric gases. While the carbon dioxide and water vapor are the direct products of the combustion process. Depending on the engine type and configuration, these harmless gases form 98-99% of an engine’s exhaust. However, the remaining 1-2% of combustion products comprise thousands of compounds, all of which to some degree, create air pollution.
The primary components of these pollutants, carbon monoxide, and nitrogen oxides, are formed within the highly reactive, high-temperature flame zone of the combustion cycle. While unburned and partially oxidized hydrocarbons tend to form near the cylinder walls where the combustion flame is quenched. Particulate matter, especially in diesel engines, is also produced in the form of soot. In addition to this, engine exhaust also contains partially burned lubricating oil, and ash from metallic additives in the lubricating oil and wear metals.
WHY CATALYTIC CONVERTERS
In 1970, the United States passed the Clean Air Act, which required all vehicles to cut its emissions by 75% in only five years and the removal of the antiknock agent, tetra-ethyl lead from most types of gasoline.
THE FIRST CONVERTER
Modern automotive catalytic converters are composed of a steel housing containing catalyst support called a substrate, that’s placed inline with an engine’s exhaust stream. Because the catalyst requires a temperature of over 450 degrees C to function, they’re generally placed as close to the engine as possible to promote rapid warm-up and heat retention.
On early catalytic converters, the catalyst media was made of pellets, placed in a packed bed. These early designs were restrictive, sounded terrible, and wore out easily. During the 1980s, this design was superseded by a cubic ceramic-based honeycomb monolithic substrate, coated in a catalyst. These new cores offered better flow and because of their much larger surface area, exposed more catalyst material to the exhaust stream. The ceramic substrate used is primarily made of a synthetic mineral known as cordierite.
TYPES OF CATS
The first generation of automotive catalytic converters worked only by oxidation. These were known as two-way converters as they could only perform two simultaneous reactions - the oxidation of carbon monoxide to carbon dioxide and the oxidation of hydrocarbons to carbon dioxide and water.
By 1981, "three-way" catalytic converters had superseded their two-way predecessor. Three-way catalytic converters induce chemical reactions that reduce nitrogen oxide to harmless nitrogen. This reaction can occur with either carbon monoxide, hydrogen, or hydrocarbons within the exhaust gas.
While three-way catalytic converters are more efficient at removing pollutants, their effectiveness is highly sensitive to the air-fuel mixture ratio. For gasoline combustion, this ratio is between 14.6 and 14.8 parts air to one part fuel. Furthermore, they need to oscillate between lean and rich mixtures within this band in order to keep both reduction and oxidation reactions running. Because of this requirement, computer-controlled closed-loop electronic fuel injection is required for their effective use.
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[@NewMind]

▶ Visit brilliant.org/NewMind to get started learning STEM for free, and the first 200 people will get 20% off their annual premium subscription

[@rajashashankgutta4334]

Yours is first comment

[@zh9664]

PLEASEEEEEEEEEEEE New Mind make part 2 of the quantum programming video PLEASE it was soooo good PLEASEEE ♥♥♥♥♥

[@jonslg240]

*The catalytic converter is a way to bring the entire cost of pollution onto the shoulders of the middle class, and even the impoverished.* It makes it so we do our part, but pay DEARLY for it, while other businesses do nothing. Even the DNC ignores pollution from huge companies, because those companies give them money via superpac's for their next election.. so they don't want to piss them off. We pay DEARLY for this, while the LARGEST polluters pay almost-NOTHING. *Leading to the obvious question: why should the middle and lower classes pay for EVERYTHING regarding pollution, while the companies that make BILLIONS do ABSOLUTELY NOTHING? Or at pretty close to nothing?* It's time to stop believing what you are told, and starting to do your own research instead.. *Because the truth is something neither party wants you to know.*

[@thesilentone4024]

I would say lead is rong but small engine planes use lead like at 2.2 grams for every gallon where in 1970s was like 0.5 or 1.1 grams for every gallon. Can you talk about thirsty cement and how it can save millions to billions of tons of sand every year and how it can recharge groundwater levels reduce flooding too.

[@wtice4632]

This isnt the most hated auto part. Diesel exhaust fluid systems are the most hated part.

[@volvo09]

Yes, cats are fine nowadays (besides people stealing them). I supercharged my car and left the factory cat in there, no need to remove it and have a smelly car. Diesel particulate filters on the other hand, those have caused headache with non stop issues, and bank breaking damage to a person with some of these trucks having almost $10k exhaust systems. (Regular trucks for pulling a trailer, not an 18 wheeler). That is insane.

[@marvintpandroid2213]

@@volvo09 10K you say? source?

[@RainOnThursday]

@@marvintpandroid2213 yeah 10k is a little steep. I paid $2700 for dpf replacement and labor and I think an scr is only around a grand on top of that. Mostly what I find annoying about the whole thing is the manufacturer warranty only coving up to 50k miles and mine went out at 58k. Up to 10 yr 150k mile replacements would be more palatable to individuals who would rather delete and pay similar money to skirt the law in search of reliability. While I don’t feel the need for more power I also don’t relish another $3000 and downtime for repairs looming at some point in the future. I’ll probably trade in for a gas engine in the next few years solely because of that

[@Hath.0]

@@volvo09 You supercharged your car before upgrading the exhaust system, AND think DPF on consumer diesel trucks cost 10k? Whew, Buddy do i have a deal for you 😏

[@PistonAvatarGuy]

@@Hath.0 "...AND think DPF on consumer diesel trucks cost 10k" He said the whole exhaust system and that's probably not too far off when you consider the entire system and the complete SCR system, which is an entire electronic injection system by itself. Heck, with all of the piping, sensors, the SCR catalyst, the SCR injection system, the DPF and the DOC, I wouldn't be surprised if that were conservative.

[@theo_korner]

Most people dont hate having a cat, but getting it stolen

[@devilsoffspring5519]

I don't like it when they hiss at me and scratch me either

[@techman2553]

There's nothing worse than cat burglars.

[@catsaregovernmentspies]

Or having your cat snitch that you didn't pay your taxes

[@AwesometownUSA]

@@catsaregovernmentspies this is dangerous misinformation, you’re clearly just a shill for the Big Dog industry & their lobbyists

[@jameskarrie298]

Or needing to get it replaced.

[@bohdanked]

Finally after many years now I understand why Air-Fuel ratio oscillates. I was always perplexed why with todays electronics they don't try to run air fuel ratio as close to perfect as possible.

[@FilipAus]

Yeah same. I always thought it was the system hunting due to delays in the ecu and sensors. Now I know better!

[@northernpatriot9078]

they do it is pulse width modulated off of O2 signal and other inputs its pretty efficient

[@northernpatriot9078]

on older systems it was called lambda

[@devilsoffspring5519]

@@northernpatriot9078 It's still lambda, the symbol for air-fuel ratio.

[@Capitanvolume]

Knock is also prevented with a richer mixture so engines often run rich under heavy load

[@johncochran8497]

Little known fact. The very name of the catalytic converter came from ignorance and fear. In a nutshell, it's a reactor that uses a catalyst to perform the chemical reactions to make the exhaust safer. So a reasonable name for the device is "catalytic reactor". But that word "reactor" caused too many people to think of "nuclear reactor" and the connotations of that, along with too many ignorant people thinking that the "catalytic reactor" would mean that it's radioactive. And that mistaken belief would cause the acceptance of the device problematic. So a different name was required. And since the device "converts" harmful emissions to safer emissions, the name selected was "catalytic converter."

[@bohdanked]

Similar to "microwave oven" instead of "electromagnetic radiation oven"

[@jhoughjr1]

@@bohdanked except, the electromagnetic radiation is an oven IS microwaves. A traditional oven isnt an infra red radiation oven either.

[@NoNameAtAll2]

reactor has been nailed to only nuclear ones everything else should be renamed

[@zlac]

Most of the world call this part "Catalyst". You had to add the extra word in USA, but you also call glasses "the eyeglasses", wheel is "the steering wheel" and many more.

[@johncochran8497]

@@zlac Oh, so what's that thing you fill with fluids such as water, milk, etc. that you drink from? And if you have several of them? As for "steering wheel", what's those things (usually 4) placed near the corners of a vehicle called?

[@freedomandguns3231]

This is not the most hated part. People LOVE catalytic converters. Havent you heard about the massive spike in cat converter theft?

[@280zjammer]

It wasn't the catalytic converter that was hated, it was the EGR valve. You might still argue that it's not something good even though the reliability issues caused by the EGR valve have been mostly fixed. The catalytic converter made cars stop stinking and deserves most of the credit for cleaner emissions from gasoline vehicles. In conjunction with fuel injection using O2 sensors, catalytic converters make the busy city much more bearable without really reducing power by anything significant. EGR valves, on the other hand, do things in the laboratory that don't reflect real operating conditions and at the end of the day, they do reduce power and efficiency while reducing engine life. I like road vehicles having catalytic converters but get rid of EGR valves already.

[@madcat4563]

I was always against removing EGRs or blanking them. After enough digging, I found out long term they are a bad thing for a diesel car, especially if it has a turbo and intercooler. It clogs up the intercooler, throttlebody, and intake manifold. I always thought a catch can would solve the problem, but after digging, I found it made it even worse.

[@patrickradcliffe3837]

I would also say smog pumps are in the same category.

[@Kj16V]

​@@madcat4563 What did you read about catch cans?

[@KenanTurkiye]

I wished they would invent a catalytic converter for the media too.

[@MattyEngland]

We're the news now, only boomers and retards believe the mainstream media these days.

[@bryanjk]

y u so racist

[@robtownsend150]

That's a tough call, in my country Def (gov juice) is probably more hated.

[@lorennicholls5901]

They might overheat!!

[@KenanTurkiye]

@@lorennicholls5901 lol good point.

[@jaromirandel543]

No. The most hated is EGR, Stop-Start and "smart charging - recharging by high above gasification voltage". Those 3 things made car's lifespan much shorter than everything.

[@kittyNya38]

That’s why I purchased a module to disable the auto start-stop feature of my car.

[@eggnogmonkey]

How does stop start reduce vehicle life? Vehicles equipped with it are either a hybrid and using the motor generator to start which is more than capable of the job or a normal ICE with a beefed up starter motor that can sustain repeated starts.

[@jaromirandel543]

@@eggnogmonkey First of all, your engine is stopped when the turbo is very hot and still rotates. That means no lubrication while it still rotates. It can take up to one minute until the turbo fully stops. Second, the accumulator is much more often under high load. The diesel particulate filter (which is mandatory also for benzine cars in EU) don't like the stop-start system.

[@jaromirandel543]

@@eggnogmonkey Also I don't like the "button" engine start. It mostly requires to press and hold the clutch pedal. That causes relatively high crankshaft bearing wear due to no oil pressure. The clutch mechanism makes pressure on crankshaft which creates high metal-metal friction at the non-lubed engine start.

[@Hath.0]

True. I hate the start-stop systems, alot of unnecessary wear on critical components. But they are made to be a maintenance item now so manufacturers can profit on high value or rather high price items. Alot of the newer vehicles don't even want the owners to do maintenance on them. Most need specialty tools or proprietary fastners. Not much is made to last anymore.

[@GalileoAV]

I love it when safety technology is so ubiquitous that it can be almost forgotten about, blending into the background.

[@mikemiller659]

Until someone steals your cat converter

[@dafalzonAUS]

Or if the engine check light comes on

[@GodKing804]

Or Mod your car

[@michaelmccarthy4615]

Or costs so much money that it isn’t worth it…

[@timault8209]

Or the ECU gacks and the exhaust is carbon laden.

[@SmokeElectronics]

I remember the smell of the trailer park I lived in in the early 90s growing up. Not smelling car exhaust is definitely worth every cat on the road. EGR is what kills engine life especially diesels

[@Look_What_I_Did]

Nope.

[@crf80fdarkdays]

​@@Look_What_I_Didyeah

[@bobbysenterprises3220]

Cool video. It's quite rare for an OBD1 vehicle to have post cat o2 sensors. I was hoping that you would touch on the widely used scheme of pre cats and a second converter. Even my 2000 has two precats (split 3 & 3 cylinders) that are mounted very close to the engine right after the exhaust manifold. Then they funnel into one larger more traditional looking cat in the normal place.

[@johnwalker194]

Are pre-cats just oxidation converters ? Meaning they are as close as possible to the exhaust valves and glow white hot and burn any remaining hydrocarbons ? Sometimes they are just scrolls of stainless steel looking material ! I know from the car salvage industry that pre-cats are usually of little value when it comes to recycling the precious metals and the real value is in the main/secondary converter !

[@mrflamewars]

The downstream (post cat) oxygen sensor isn't just checking the level of oxygen in the exhaust - it's used to check that the oscillation between rich and lean is not visible behind the cat as the cat processes everything. Anyone who wants to watch their car working should get an ELM327 device and read the OBD2 Live Data with it.

[@seymoarsalvage]

I just converted my truck to carb got rid of all that computer crap

[@albubbles9232]

@@seymoarsalvage. Neanderthal

[@mrflamewars]

@@seymoarsalvage Well isn't that special. Congratulations on being a luddite I guess?

[@branpod]

At scale, I think most people appreciate the benefits of them. Most just get annoyed at having them stolen or having to pay a ton to have an inessential part replaced (in states that require them).

[@UCs6ktlulE5BEeb3vBBOu6DQ]

As a tuner (megasquirt etc) that had many turbo cars, I ALWAYS loved cat converters. I dont care losing some power to it. Start a tuned car without one in a underground parking and you'll know why I love them.

[@stevey500]

I bought a truck that had hollowed catalytic converters and it was an awful experience starting that truck on a cold morning in a parking garage or any other partially enclosed space and it was just a 4L v6. I can't imagine the awful emissions from larger engines with chopped emissions systems. A agree that a properly dialed in emissions system is something to be highly thankful for.

[@rickrutledge9363]

They're heavy, they get too hot, and they cause back pressure. They suck.

[@Meekmillan]

Yeahhh I ran catless bc POWA (marginal since I’m NA lmao) and it was awful at long stoplights, not to mention loud as shit lol Welded some new ones in my down pipes and all is well

[@PURENT]

The stank of a cold start except all the time.

[@misterdeedeedee]

modern cats are surprisingly very good for government mandated emissions equipment. my first car I ran catless because you know 19 year old and while there was a little boost in power and throttle response (at least according to the butt dyno), the smell always sucked. when I eventually got rid of that one and got another car, I did a nice exhaust again but I put in high flow cats and it got me 95% the expected gains with 0% of the smell.

[@hondaguy9153]

I hate how many people bitch about emissions controls because they vastly reduce emissions and hardly impact performance until you're trying to double or triple the output of the engine and if you're doing that you shouldn't be driving it on the road. The engines that have issues with EGR and DEF I get are frustrating but that's due to shitty designs, not the existence of that emissions control.

[@timault8209]

ALWAYS an excellent production from this guy. New Mind is a great product.

[@marvintpandroid2213]

How quickly we forget what big city air was like in the 1970s

[@downstream0114]

Look at China before bitching about catalytic converters.

[@marvintpandroid2213]

@@downstream0114 Any point you want to make rather than just shout CYNA ?

[@jhoughjr1]

any time I went to the country from st Louis, I was all "Man U digging this air?" the difference is amazing.

[@jhoughjr1]

@@marvintpandroid2213 U wanna actually look at the places he is talking about? China has basically zero environmental protections.

[@berrigo2]

@@marvintpandroid2213 China currently has rampant air pollution due to lack of environmental regulation. It's literally the point. Look at Chinese cities they are buried in a cloud of smog

[@video99couk]

My 1994 Toyota Celica is still passing the stringent MOT tests in the UK, with its original catalytic converter installed.

[@johnwalker194]

A thousand cat converter thieves want to know your location now ! Big money in those "Japanese" cats of that era ! 😉

[@fjshdf]

I'm told by my mother an asian marketplace near me was actually a front for a catalytic converter theft organization. Apparently the guy who ran one of the restaurants with really good rice got his house raided and they found like four pallets worth of stolen converters. Wild. I mean, they're not gonna lose my business, it's really good rice and I can't find those spicy shrimp chimps anywhere else in town, but still crazy.

[@JUSTENization]

As always, awesome illustrations and explanations. Thank you.

[@mereal250]

My favorite fact from this video is that some diesel engines now run on Piss.

[@wtice4632]

They dont run on piss. Theyre mandated to periodically burn piss in the exhaust.

[@alexrogers777]

Good video, wouldn't have minded a more in depth explaination of how the reduction and oxidation reactions work, like the chemistry of them

[@edwinwise6751]

When I moved to San Jose in 1970 you couldn’t see the east foothills except after it rained.20 years later after cat conv.most of the smog had gone and hills retuned. Check out old reruns of dragnet on location street scenes , visibility is about 1 block

[@ailtonjose3079]

A piece that saved hundreds of thousands of people from suffering from respiratory illnesses.

[@bleuebloom]

npc comment

[@__prometheus__]

@@bleuebloom ironic

[@MayankPrasad111]

Stunning and brave.

[@MattyEngland]

You forget the Ukrainian flag

[@v3n0x]

And counting

[@davidg3283]

To anyone questioning modern pollution controls on cars I suggest you attend a classic car meet and stand close by at the end when all the old cars line up to leave. Take a good deep breath as they drive by.

[@lorennicholls5901]

As my eyes burn as well.....

[@CaptainBlitz]

Then enjoy casually getting caner whilst bitching about pollution 💀

[@dixiefire1337]

the people who sniffed exhaust fumes to tune a carb were the ones that put men on the moon but here we are worrying about smog in la

[@gesamtszenario]

@@dixiefire1337 The same generation of engineers who put men on the moon where the ones to worry about smog, and develop emissions control technology in the first place.

[@TheCatOfAges]

Mmm, delicious

[@eds6889]

Excellent explanation and video. Thanks for your hard work. You have me as a new subscriber.

[@TheMadTube]

I was a master automotive technician for 15 years. Whilst I absolutely lament the problems newer diesel vehicles have with their catalyst and emissions systems, I feel it is the greatest single thing that made vehicles better. Just the smell that accumulates on my clothing after working around non-catalyst vehicles can make me nauseous, so it has saved countless lives by reducing harmful pollutants. But we are still burning dead dinosaurs, so there’s that.

[@Willam_J]

Hey! You’re just the person, who could answer this question for me. I’m not an idiot with a wrench, and have built a few engines, years ago, but my degrees are in Electronics Engineering and Physics. Anyway… When I lived in Chicago, I had to take my car to have the emissions test performed. At the time, I was driving a 1985 Ford Escort. No matter what I did, it would ALWAYS fail the test. I performed tune-ups, changed filters, drove it on the highway to warm it up, etc. One day, I had failed my third attempt and was instructed to go inside and talk to someone. The guy that I spoke to, told me to change my oil, right before bringing it there. I did that, and it passed with room to spare. I always changed my oil, at regular intervals, but something about oil, with some use on it, would cause the car to fail. I have a few theories. I’ll mention them, but I’m open to the opinion of someone who does this for a living. 1. The increased viscosity of the new oil, provided better compression and better efficiency. 2. There were contaminants in the oil, which made their way through the combustion chambers and exhaust system. That’s all I’ve got, but I’m definitely open to other explanations. From that day on, i changed my oil right before the test, and never failed an emissions test, again. (This might also be useful, for someone having the same problem. Who knows, right?) Thanks in advance! Take care! 😃

[@TheMadTube]

On average, engine oil is diluted with about 10-15% fuel and combustion material when you change it. That’s because no matter how good your piston rings are, some oil is lost in combustion. That works both ways, as fuel gets into the oil. For the most part, it balances out on good running engines where the fuel dilution is matched by amount of oil lost in combustion. As your oil gets more miles on it, it gets dirtier with wear and combustion products. That increased dirt is being cycled back into the combustion chamber to be burned, creating a small feedback loop. Fresh oil has less combustion products.

[@Willam_J]

@@TheMadTube - Thanks for the reply. I knew that I was on the right track, but it’s nice to have it confirmed/explained. Again, thank you and take care! You’re awesome! 😃👍

[@andrewb8548]

I was talking to a guy who was the Northeast US sales manager for a major equipment manufacturer and asked him which model I should buy for non-commercial use. He looked both ways and whispered, used pre-epa 3 years at the time (off road diesel engine this was like 2010). He went on to explain that the best that they or anyone else could do was assume the warranty rate would approach 100%, so they added $7000 to the msrp to pay for it twice during the warranty period. As I wasn't going to run it daily the warranty would expire before I took advantage of the 2 extra catalytic converters I'd already paid for, and once it went I'd be stuck paying $3500 because the computer would shut it down once the check engine light was on for several hours.

[@merevial]

I needed this today.

[@ryanle1293]

I think the one sparkplug that just had to be behind literally every other part that's been seized for god knows how long is my most hated car part

[@ricepony33]

Pre heating cats with a simple fuel/spark combo similar to a garage rocket heater would work extremely well. It would also save engines wear and tear from cold start high rpm running.

[@stevey500]

I believe diesel emissions control systems do something similar to this. Some of them have a fuel injector in the exhaust system.

[@SGTECH-di9df]

Toyota has a strange system on their vehicle that routes coolant lines around the outlet of the CAT that helps warm the engine faster so the engine can warm the CAT up in this way instead. It also had a switch that was physically moved by the temperature change to turn on/off the system automatically, really different thinking on that one. As an added benefit the engine now operates more often in it's normal operating temperature and has less internal "wear and tear"!

[@stevey500]

@@SGTECH-di9df that’s quite wild. Cool to know! Thanks!

[@Nickfromcali]

Ok, but how much pollution was caused mining those 3 minerals?

[@johnsamuel1999]

But any pollution casued would be at the site of mining and refining. So the pollution in cities is reduced

[@Nickfromcali]

@@johnsamuel1999 Out of sight, out of mind eh?

[@johnsamuel1999]

@@Nickfromcali yes , thats why a lot of stuff we consume is made in china or the rest of asia (they have weaker environmental laws )

[@PURENT]

@@Nickfromcali Like a no smoking zone.

[@Nickfromcali]

@@johnsamuel1999 I hate to break it to you, but we're on the same planet as Asia. Which means we share pollution

[@nates1one1]

Great video! But I'm wondering, how much fuel is used to mine these rare earth metals to build and ship these cats? To only get a 40% decrease of emissions.

[@gotworc]

Given that you can go to a place like LA or NYC or pretty much anywhere in the US without there being smog that looks like thick layers of fog I'd say the net positive is greater than the net negative

[@Likeomgitznich]

Not to be “that guy” but a catalytic converter doesn’t cause check engine lights, the emission sensors do.

[@devilsoffspring5519]

That's right, the converter itself has no signal output of any kind that the ECU can detect and process. It's the O2 sensors themselves that detect the emissions fault condition and not the cat.

[@nolanmitchell7319]

The egr and dpf systems are over in the corner like hold by beer, they literally caused an entirely new market for deleting diesel's cause they were so hated by consumers.

[@DustyTheDog]

I got lucky and didn't have to pay to replace my CC. There was a federal recall on the CC in my vehicle. So, at around 130k miles I went and got a new one for free. It was nice 👍👍👍👍

[@xeonthemechdragon]

Such a simple component that does so much for emissions

[@jaredkennedy6576]

I don't think I've ever seen an OBD 1 system that had catalyst monitoring. This was mandated with OBDII, and car manufacturers are loathe to do anything without being required to. The monitoring is pretty basic, too, usually it's just the computer watching for the rich-lean swing of both upstream and downstream sensors, and if the downstream one moves too much it'll set a P0420/P0430 code.

[@SGTECH-di9df]

The CAT monitoring system is simple in concept but does a great job. The O2 sensors are actually one of the main systems used to monitor how the engine is operating in general and gives a lot of information when trying to find what is causing the sensors to read out of spec measurements for normal operation. The CAT monitoring system is not just monitoring rich to lean movements though, its making a calculation of how much of the pollutants are being converted and comparing those reading against all the other sensors on the car and the PCM crunches the numbers and if they dance than the CAT monitor on your car passes another day.

[@neddyladdy]

Wow, I never knew there were surveys about car parts. and hate.

[@ericjennings853]

Its amazing the difference in the air quality when i travel to a 3rd world country walking around on the street the emissions are really bad from passing buses and trucks, also their gas stations have no vapor recovery systems on the fuel pump nozzles. My lady friend in the philippines and her sisters seem to all have athsma.

[@h.d.h]

I ride motorcycles. So many bikers take off the cat and I wonder if they've ever traveled to a country where they don't have cats. Foolish assholes.

[@khysor1832]

I always remove them. Better to have them safe in my house rather than being stolen 😂

[@volodumurkalunyak4651]

Insane decision. Catalytic converter inside your house is as userfull as stolen one. Furthermore you have to spend money upfront (NOT later or NEVER) removing one and making cars computer accepting that.

[@khysor1832]

@@volodumurkalunyak4651 been running solid for a catless downpipe for $200.

[@volodumurkalunyak4651]

@@khysor1832 $200 down the drain. Even more if you value you'r lungs.

[@khysor1832]

@@volodumurkalunyak4651 car goes vroom 🏎️

[@volodumurkalunyak4651]

@@khysor1832 no, it doesn't. It isnt a F1 car therefore it doesn't do wroom. Only Formula1 can go vroom.😎😁😁

[@charleshines8523]

I only hate catalytic converters because many people get them stolen from their vehicles. I live in the styx somewhere and thus it is extremely rare to have a thing like that happen out here, especially when you have the vehicle in a garage. Perhaps it is one of the reasons some insurance companies have discounts for keeping a vehicle in a garage. It would only make sense since a vehicle in a garage would be less likely to be damaged in bad weather, vandalized, stolen or broken into by thieves looking for cash and valuables. Also my garage doors have locks that can slide into the side rails and make it just about impossible to open them. These also take a fair bit of force to operate so I seriously doubt a coat hanger would easily move them. They are good to have if you had a power outage and had to leave the house. You would use the emergence red handle to unlock it from the opener and manually open it then manually close it once the vehicle is out. You would just have to use the locks mentioned earlier to keep the doors from being opened. I like to unplug the opener so I don't mistakenly try to open the door while the locks are in use because it will not damage the door but it can make it really hard to undo the locks. I just use the front door to get back in whenever such a rare occurrence of a power outage happens with me needing to go some place.

[@that_hoser_143]

I like how you release this video the day that I broke my sensor

[@WarmWeatherGuy]

What is the frequency of the oscillation between lean and rich mixtures? Once per day? 100 times per second?

[@mcspikesky]

PPF and DPF seems like a good topic but you're surely on it!

[@punditgi]

Excellent video!

[@crazypete3759]

The problem is the EPA turns this into a compliance issue instead of a measure of pollutants. They make it a crime to modify any emissions components, regardless of the outcome. If someone installs a high performance catalytic converter, that improves performance and emissions reduction, the EPA still considers that illegal! Even if you take it to an emissions testing place and show that the new system functions better, the EPA still says that is illegal! They don't care about complying with emissions standards, they only care about complying with their definitions and requirements so they can keep all the emissions companies making billions and billions of dollars! In commiefornia a stolen catalytic converter from a Toyota Prius can cost over $3000 to replace since you are required to use OEM parts, in other, more normal places, it would only cost $300-$500 since you can use any generic catalytic converter, and it works just the same, emissions results are the same. They need to stop focusing on compliance and bring back real testing!

[@PURENT]

"High performance" catalytic converters increase emissions in exchange for performance. There is no way you're getting a catalytic converter that gives you better flow AND less than or equal emissions as stock. Most aftermarket ones are inadequate because they do cost cutting, the price in these things is all rare metals and if you're getting them for cheap you're not getting nearly as much rare metals in them.

[@PURENT]

@@hops4656 Yeah if everyone used those cheap cats. The smog would be less than the 70s but more than now. It would also be noticeably smellier.

[@JohnS-il1dr]

You pay a thousand bucks to have that CA Compliant emblem stamped on a generic CAT that goes for 200 dollars in the other 47 states.

[@crazypete3759]

@@JohnS-il1dr it's all a big cash grab!

[@smd-tech]

​@@PURENTlarger surface area cat can give better flow while still retaining conversion efficiency, at the cost of being more expensive as there is more material in it and being harder to fit in the available space. But yes a lot of the cats marketed as performance cats are not as efficient.

[@extremerc76]

My cat got stolen, insurance wouldn’t cover it… $2k, to replace cats on a $3k truck, now I’m straight piped! Lol

[@JohnS-il1dr]

Lucky you don't live in Cali. That's a huge fine if you get caught here.

[@CrazyBear65]

I had a 78 Nova with one of those restrictive pellet-type cats on it. I took it off, emptied all the little bbs out of it so that it was just an empty can, and then put it back on the exhaust. Any restriction Big Brother can think up to oppress the people with can be defeated by a smart individual. Long live classic American musclecars!

[@rickintexas1584]

I remember the first time I went to Los Angeles in the late 80s. The air quality was horrible. Catalytic converters definitely played a part in making LA a little better.

[@billrowan1957]

I think registration and mandatory insurance is the most hated auto part...

[@totallyrandomuser5760]

Cats would be the only exhaust part I'd keep from original if I were to straight pipe

[@HelloKittyFanMan.]

"Myriad" isn't correctly used in "A myriad of of trace compounds are also present." FFR, it would be "Myriad trace compounds are also present."

[@arpankoley5245]

Why are you not in Nebula, my friend? You have been making extremely informative videos. I genuinely suggest you to have a look on curiosity stream+ nebula package.

[@Anon-.-]

Genuinely amazing content on automotive engineering. Why are you focusing on soon to be redundant technology? Battery science and edu engineering is fascinating!

[@keitha.9788]

I grew up in southern California during the 1950's, 1960's, and early 1970's.. In the 1950's the smog seemed to burn my eyes and throat. By the end of the 60's, smog had changed. Although still quite visible, it didn't seem to burn my eyes and throat nearly as badly as years earlier in the 1950's.....

[@jonathankidwell6889]

Very interesting. Definitely expanded my knowledge on the subject. I've heard that the the net manufacturing foot print of catalytic converters approaches canceling out the benefit. But it's something I take with a grain of salt, although I'm sure the footprint of mining the precious metals and manufacturing the converters must be substantial. It would have been interesting to hear something about their footprint as well.

[@ct1762]

right but its nothing compared to BEV's. of course the real polluter isnt emissions. it hasnt been for over a decade as gasoline cars are so clean, its a non-issue. the big polluter is actually the toxic rubber in tires. EV's are much heavier, thus requiring replacement tires much more frequently, and wearing out roads much faster.

[@epixtille7069]

@@ct1762 that's the dumbest take I've ever heard

[@ThatOneGuyWithTheEye]

They are ridiculously expensive in CA taxed into oblivion I got the same cat replacement shipped to Arizona for like $150 for my silverado and it passed perfectly the same exact cat that was "CA compliant" and able to be shipped to California cost over 1k

[@wolfmantroy6601]

Move outa that shjt hole

[@alb12345672]

The cats are probably the same because people may take a carb car out of CA with OBD checks, and there are states that have similar requirements BUT the CARB kosher symbol cost a fortune.

[@dallynsr]

Easy solution is to stop voting Democrat, And of course then move out of California. And absolutely in that order.

[@Look_What_I_Did]

@@dallynsr Every body move to where dick head Dave lives. Turn it blue.

[@hankkingsley9300]

Thank God I live where there are no inspections whatsoever

[@sunnohh]

Cats are cool, plus they don’t really hurt performance anymore

[@TBrady]

This isn't the most hated part, EGR coolers are.

[@who2u333]

If you want to experience pre-catalytic converter air quality, spend a few days in Havana. It's an interesting experience.

[@devilsoffspring5519]

The hallucinations from inhaling the air are interesting? ;)

[@gregorymalchuk272]

Apparently the original American gasoline engines on those old cars have long since worn out and have been replaced by Soviet diesel engines.

[@josron6088]

I've been working on my own car since I was 16 im 52. The problem some catalytic converters (if bad) there hard to get to, difficult to take off. Bolts and nuts fuse into place and break off. Expensive to pay a shop to do the work for you.

[@lr937]

Only one benefiting from it is the thieves going around stealing them

[@zacharytuttle5618]

My cat went bad in my lexus gs350 and that error code causes the traction control to turn off until its resolved. That's ridiculous.

[@MaakaSakuranbo]

I mean, if it doesn't, people will just going to ignore it. "eh, it works!"

[@marvintpandroid2213]

Your whole car should shut off.

[@volvo09]

The interconnectivity of the systems in modern cars is crazy. One engine "related" fault and all interconnected systems are disabled. Traction control, stability control, cruise, remote start, it all depends on the brand, and how new the car is. The newer the vehicle, the worse it is. On some GM vehicles the AC is disabled.

[@wtice4632]

O2 sensor faults cause my VSC and traction to turn off too. Any engine code does for some reason

[@volvo09]

@@MaakaSakuranbo that's up to the states to enforce. That's why you have annual inspections. Can't pass with a bad cat.

[@gradypicinich2404]

Ugh don't even get me started on blinker fluid

[@paul_109]

The most hated part is easily the EGR, not only does it nothing to improve the performance, it actually shortens your engine's lifespan and costs you a metric shitton of money

[@rock-uu7qr]

Egr dpf and def are the much more hated components

[@Akac3sh]

I just hate how expensive they are. Especially primary cats. Had to pay 3000 to get them repaired

[@Willam_J]

OK… I’ll admit it. I’ve heard of ‘diesel exhaust fluid’, but I wasn’t completely sure if it was a joke, like ‘blinker fluid’ or ‘muffler bearings’. 😂 Fun fact: The Diesel engine was invented by Rudolf Diesel. The original Diesel engines were designed to run on peanut oil. It wasn’t until years later, that Diesel fuel was made from petroleum. The next time someone talks about recycling cooking oils, and processing them into Bio-Diesel fuel, you can tell the that their idea is more than a century old. The Diesel engine was named after the man who invented it, not the fuel that it uses. Bonus fact: Gasoline (petrol) engines were originally designed to run on benzene. Extra Bonus Fact: The very first cars were electric and ran on batteries. This was first done, back in 1828. We’ve come full circle, in so many ways. Extra Extra Bonus Fact: If you watch this KZbin channel, you have an inquisitive mind. Don’t *ever* stop learning! Stay awesome, my friends! 😃👍

[@0neIntangible]

How about seasonally changing from summer air to winter air in your tires.

[@windhelmguard5295]

pretty sure the very first cars had steam engines.

[@LectronCircuits]

As always, it's better to have gas than to have a gas problem. Audience is completely exhausted. Cheers!

[@wannabeetiger]

Actually the Catalytic converter is definitely not the most hated part , cuz when I'm ready to scrap my car that's the first thing I'm going to cash in on. Besides, most people aren't trying to go race their car and have all the power they need, so they do not care if it's on there anyway. This is where government care and control with the EPA takes over.

[@mikeydude750]

The EPA is absolutely lying about those health outcomes.

[@chevyboyforlife4234]

It robs power ...Im glad I live in Florida you don't have to have them on you car

[@boowiebear]

Many people are doing cat deletes…unfortunately not of their own choice.

[@tjones261]

People only hate the catalytic converter because as the narrator said, it doesn't improve the cars performance for the car owner. What it DOES do is COST a lots of money as mechanics shoot expensive replacement parts at the car while trying to get the "engine light" to go out so the car can finally pass inspection.

[@MrMaelstrom07]

The Answers with Joe on leaded fuel was fascinating. I don't remember what it was called, something like the man who killed millions.

[@ThunderSims]

The thumbnail for this video made me want maraschino cherries

[@circusmaximus72060]

Pffft the most hated emission equipment is the SCR systems on diesel trucks.

[@regularpit1508]

Where we live there's no emissions tests and I can assure you my car and many of our others do not pass. So that statistics is probably right on what they surveyed but I would say it's much higher. Also vehicle 25 and older I think it is can get away without a catalytic converter.

[@P_RO_]

No inspections in SC and probably never will be. We lose some Fed hwy funding because of that. Far nicer to not have the Governmnet's nose in our business and well worth the small cost 😁

[@jimmyhuesandthehouserocker1069]

When I was a kid, I told everybody when I grew up, I was going to be a scientist-chemist. I never made it, mostly because my dad Herb demanded I work for a living in factories, the way he had to do. He was jealous of college people because they had an easier life and more money than her did. Yeah, but I've still always been interested in the kinds of things like this video, science 'n applied chemistry

[@kevinwalsh2922]

Never too late. Good luck buddy!

[@GUSftw]

now let's compare automobile emissions to barge ships at sea.

[@HiatusMobs]

EGR’s for sure the most hated.

[@markst.germain9286]

Love the Smell of a car without one.

[@bledlbledlbledl]

(thumbnail-pic) no wonder the cat goes bad; those cranberries are gonna spoil after a while :P

[@shangri-la-la-la]

Spark plug defowlers are not just for spark plugs. Try them the next time you have a 420 code.

[@P_RO_]

Just one downstream...

[@foracal5608]

100,000 live? I think it's more than that. But huh I knew it was on the fly chemically changing the bad stuff but now I know more about it.

[@alg003]

And yet enormous ships burn millions of barrels of crude oil, instead of using safe, proven nuclear power, there are no restrictions for the US military vehicles, and it's being blamed on the average consumer, and we're told to pay 6 figures for an electric car with horrid ranges, reliability, and repairablility.

[@lorennicholls5901]

And they spray pollutants in the air all the time

[@homuraakemi9556]

Technically they burn marine diesel fuel, but I'm with you

[@UQRXD]

Is the stuff inside a catalytic converter toxic? Indeed, every modern car equipped with autocatalysts may release toxic heavy metals during engine operation. This fact hasn't been widely discussed and remains underestimated. Jan 14, 2016

[@shmookins]

Why is it hated? I never think about it and it isn't one of those parts that fail and need replacements enough times for most people to even know what it is.

[@fartpluswetone8077]

Only problem is, when they do fail, they render the car effectively inoperable (because it won't pass inspection in pretty much all states and thus can't be registered) and are very expensive to replace all for one part.

[@moisesisairocha]

5:53 missing finger!!!

[@reelgotmarko]

Very, very observant

[@blackpantherjon9709]

my 1997 jeep had one cat, pushed it to 92mph and the cat blew up 😂. took it off and straight piped it to the muffler, since vehicles older than 25 years old don’t need a cat in VA. doesn’t smell great but somehow better than it did before it blew.

[@workinprogress3942]

Trick question. Could be the converter or def or ecm or paint or tires. Seems like the most hated part would be the one your fighting against.

[@Altezza1999]

I'm pretty sure that title belongs to lane keep assist and in the future those alcohol level checkers and speed limiters that will forcefully slow the car down.

[@piedpiper1172]

Buddy, why do you hate alcohol checkers? You do that much drunk driving?

[@Ass_of_Amalek]

dude, leaded gasoline even prevented the implementation of catalytic converters? that's so f°°°ed up!

[@microdesigns2000]

When I was a child, cars were stinky and the exhaust made me choke all the time. I did not understand catalytic converters were the reason that problem went away. This is the best video I've seen on the subject. Over the years I realized I can tell brands of cars from each other by the smell from the exhaust. GM smells different than Toyota, than Chrysler than Ford. Probably this is variation on the catalyst used.

[@heyitsfranklynn168]

Why does the repair bill top out at $2700? 🤣

[@BigBoss1292]

I think they were hated in 1975 because they were the cherry on top to the disappointment cake of stricter emission standards and detuned engines that plagued the early 70s

[@kenmohler4081]

I made the mistake of buying a new car in 1974, the height of detaining to meet emission standards. A 350 cubic inch (5.7l) engine producing around 140 horsepower and getting 8 to 10 miles per gallon. Today my car has a 3.6l engine producing 310 horsepower and delivering over 30 miles per gallon on the highway. You won’t convince me that catalytic converters weren’t the way to go.

[@oliverklozov]

Very nice

[@rajashashankgutta4334]

Yours is second comment