Comment by MBCook
15 days ago
The number of ICE cars I get stuck behind from time to time that just REEK is amazing. I’m in a decently well off area too.
Some putting off soot clouds, white smoke, nothing visible but clearly not doing complete combustion. Sometimes I wonder if half the cylinders are even working.
I’ve heard one car like that is the equivalent of a surprisingly large number of modern ICE cars is in good shape.
I love EVs. I’ve had one for 5 years now, and I’m glad they help. But I think the “are new EVs worse than new ICE” discussions so often miss a fact.
The pollution from ICE isn’t just from very modern well tuned vehicles, things vary wildly. But all EVs use the same power supply (assuming local grid only), so no individual vehicles put off 10x the pollution per kWh.
My city is covered by a low emissions zone so the odd van polluting sticks out. I was in Athens recently and the pollution from so many old rough cars was so noticeable (and quite unpleasant).
Reminds me of how I didn't really notice cigarettes until they were banned from public spaces and the base level of normal was recalibrated.
Many car enthusiasts remove the catalytic converter for a combination of additional power and/or better sound. It has a massive impact on emissions and what you might be smelling is hydrogen sulfide which is normally converted to sulfur dioxide which is orderless.
I should note the power increase may not have a major impact on newer cars where the cat has been optimized to reduce it's negative power impact.
Infact a popular tuner company, APR, that provides flashes tested the recent Volkswagen GTI and R generation with their most common tune and determined that with their tune removing the cat had a nominal impact.
*Basically they can bring the cars power as high as the OEM internals can handle reliably while keeping the cat. There are cars where it still has some impact and of course, different from power ,"straight piping" a car can offer a subjective sound change.
For every car enthusiast there are probably a hundred poorly maintained vehicles on the road. Black smoke is likely soot, and white smoke is almost certainly an oil leak.
Oil in the exhaust in quantities high enough to produce acrid white smoke is extremely common on a number of ICE engines, like blown head gaskets on E25s (found in most Subarus before their Toyota involvement in 2010) for example
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> Infact a popular tuner company, APR, that provides flashes tested the recent Volkswagen GTI and R generation with their most common tune and determined that with their tune removing the cat had a nominal impact.
Do you mean minimal impact?
Yes. I made a mistake in how I worded that. They are able to tune to other bottlenecks in the car while keeping the cat.
Probably. I read it as “had an impact but kept the performance stayed nominal.”
As someone into performance cars and motorcycles, removing a cat is pretty uncommon, and you're generally seen as a dick if you do it.
There are a lot of "street mechanics" who will remove your cat for free without even needing to ask.
I could see a single "bad" ICE car being the equivalent of 100 "good" ICE cars. Even the VW emissions scandal (where the cars were still functioning as designed, just not as well as they should) had instances where pollutants were 35x higher than they should be. So I could see an emissions deleted diesel (of which there are many, i.e. catalytic converter and DPF removed) could easily have more than 100x the usual emissions of noxious substances. Maybe even more! Especially if (as is often the case) the DPF was removed because something is faulty on the engine and was overwhelming the capacity of the DPF in the first place.
You can smell these cars from halfway up the road sometimes, when they're 100 metres ahead.
I don’t have hard numbers on this, but I once read a claims that the lawnmowers and weed-whackers in California with their two-stroke engines are responsible for more nitrate and particulate emissions than all the cars and trucks in the state put together, even though by fuel burned the latter outnumbers the former by orders of magnitude. I could totally see a malfunctioning four-stroke ICE with dirty burns being worse than 100 maintained ones.
That probably explains why California banned the sale of gas powered leaf blowers, law mowers, and weed whackers in 2024. You can still use them if you have an old one or by one out of state.
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> the lawnmowers and weed-whackers in California with their two-stroke engines
What's the intended precedence in that sentence?
I ask because I've never seen a lawnmower (in the US) with a two-stroke engine. There are probably some, but they're not common.
Even modern cars pollute a lot (especially in winter) because you need a certain temperature for the cats to start working. On short city trips it happens frequently that you never reach proper operating temperatures.
I used to work for the Air Resources Board of California, and while there is a warm-up period, modern ice cars are so profoundly cleaner than cars even from the early 2000s. It’s pretty stunning.
Regardless, there’s nothing cleaner than no combustion, and I can’t wait until EV‘s have replaced them all
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Yes, any cyclist daring to drive in winter can easily confirm this. It is so disgusting (and unhealthy) having to stand behind a ICE car on a traffic light and being behind a electric car is such a relief, that thoughts of wishing to ban all ICE cars as soon as possible (at least in cities) come automatically.
The tire dust crossing the bridge that's next to four lines of heavy traffic isn't much better than the exhaust fumes IME.
Buses are my nemesis. Some of the dirtiest exhaust on the roads.
Modern ICE cars have auto start/stop systems, so on a traffic light it has as much exhaust as an EV.
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You could run them on propane, which doesn't need the catastrophic converters - they make no difference at all if there's no CO or HC in the exhaust stream.
You've got the added bonus that you don't need to strip-mine huge chunks of Africa for precious metals, too.
I try to keep my cat indoors, but he won't work anyway. Maybe I should get one of those newer electric cats.
Speaking of smells....
One good thing about driving an EV is that weird oil or hot coolant smells are from someone else's car (and not a problem with your car)
(although yes technically many EVs have coolant loops)
As an aside, I'd like to mention that like 9 times out of 10 if you are driving down the road in an ICE vehicle and smell weird oil or hot coolant smells you are smelling someone else's car. The wind blows away a lot of your own stink before it gets to you. I learned to ignore anything that didn't smell 1) when I was stopped, and 2) more than once in totally different locations. After trying to track down smells that I thought were mine and were invariably from someone else nearby.
I’ve driven an EV for 5 years now, and I still occasionally think it’s something wrong with my car, instinctively lol
As the fleet of EV's age, I'm sure we'll see equivalents...
"The high voltage wires were just dragging on the street sparking, presumably with all the safety features disabled"
"They were driving with a 10 gallon coolant tank on the roof, presumably because the coolant loop had a big leak and needed continuous topping up".
If your high voltage line is conducting enough to the ground that it's sparking, your vehicle isn't going to work. Electricity follows the path of least resistance and a path to ground is a lot lower resistance than a motor coil.
EVs eliminate a lot of polluting failure states of ICE vehicles. There just simply aren't that many things to burn or leak and still have a functioning vehicle.
You're not allowed to drive cars like that in a functional society. When you go for your compulsory car checkup it wouldn't pass the required safety standards.
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Unlikely. Many of these sensors are mostly CAN-based, rather than hardwired. It would be a time consuming enterprise to custom bake a solution for each vehicle model to fake out protection systems. For better or worse EVs are substantially more difficult to modify than typical ICE.
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Where I live there are yearly check ups that you need to do, or you simply cant legally drive your car
Most EVs have lockouts that will be very hard to bypass for things like this.
It’s more ‘I could have replaced a few cells in my battery pack, but the car bricked itself when I opened the pack! Assholes!’.
Notably many recent ICE cars aren’t much better.
Are those even user serviceable? So, it won't stop everyone but it will stop most of them.
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I'd say that putting off sooth clouds is a way to sequester carbon (which obviously failed to burn). Such over-enriched fuel mixes must generate much more CO though, and I wonder if those who "tune" their cars like so take care about the catalytic converter :(
The health consequences of inhaling exhaust particulates are far more harmful than the equivalent CO2 contribution to greenhouse effect warming unfortunately.
All in all, a well tuned ICE is better for everyone than a poorly tuned one, if you had to pick between the two.
> The health consequences of inhaling exhaust particulates are far more harmful than the equivalent CO2 contribution to greenhouse effect warming unfortunately
Short term for the individual definitely, but long term for all individuals affected?
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I know in some car tuning circles, or even just blue collar Joes in some places, will recommend removing the catalytic converter. Supposedly it makes the car use less fuel at the cost of worse emissions, and can make it sound better for those who care about that.
Depending on the type of catalytic converter, both of those things can be true.
> get stuck behind from time to time that just REEK is amazing
It’s crazy. How do we even allow selling cars without HEPA filters.
HEPA filters stop dust particles and not those tiny organic molecules that cause the smells. Filters for these exist as well, usually used in respirators, but those need to be exchanged pretty frequently and are not cheap.
Activated charcoal filters are a common option even out of the factory, and I’d be surprised if there were a car you can’t get them aftermarket. They don’t last that long but honestly I’d recommend swapping the cabin filter yearly anyway.
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I never smell anything in my Tesla. Only my own farts.
We love privatising the benefits and socialising the harms of everything.
If the exhaust had to go through the cabin so the driver got the worst of it, car exhaust would be the cleanest air on the planet within months and/or alternatives to cars would rocket.
But as long as it’s other peoples health affected, meh.
> If the exhaust had to go through the cabin so the driver got the worst of it, car exhaust would be the cleanest air on the planet within months and/or alternatives to cars would rocket.
This is why forklift trucks and Zambonis run on propane instead of petrol or diesel. If you burn gas, you get no carbon monoxide or unburnt fuel because it runs ever so slightly lean and all the fuel is burnt.
This means keeping the air clear is just a case of getting rid of carbon dioxide and water, so you can open some vents (warehouses have great big vents, big enough for trucks to drive in and out...) and let the place air out. You won't die if you breathe it, unlike the CO and unburnt fuel from petrol and diesel engines.
It's a simple and inexpensive conversion, too.
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I feel like ICE cars put out such a quantity of exhaust that any HEPA filter you put on it would reach its end of life within a few hours of driving.
We have mandatory inspection of road vehicles almost every year and we measure exhaust as part of it.
White smoke is water vapor. It's a normal byproduct of hydrocarbon combustion and tends to condense in the exhaust at low loads or immediately after exiting the exhaust, especially in colder temperatures, so you'll see a lot of it in stop and go traffic.
If it "reeks" though it's not just water vapor. I see a lot of these cars too, and you can tell it's been going on for a long time when the back of the car is covered in a layer of black grime. I think that's what kind of car problem the post is referring to.
> White smoke is water vapor.
Could also be coolant or oil
Even the faintest bit of oil will turn the smoke blue.
Could be coolant, but "coolant into engine" failure modes are generally rare and are usually the kind of thing that needs to get fixed promptly.
Coolant will have the dead giveaway sweet smell.
tragically, because of efficiency standards, modern engines are known to burn oil .
Otherwise you may be smelling cars who have had the cats stolen.
Stolen cars, exhaust leaks before the cat, incomplete combustion so bad the cat can’t cover it up. I assume it’s stuff like that.
It’s not whatever tiny bit of oil gets burned in a healthy engine.
Incomplete combustion will ruin a cat. That's not its purpose, it's there to reduce NOx emissions.
A lot of old cars also since new cars are so expensive.
Yep. My newest car is over 20 years old. May be a bit more polluting (though it doesn't smell or smoke) but I've in theory saved the environmental impact of the manufacture of one or two new cars by keeping the old one.
I'm not spending $30-40k or more on a car. That just isn't going to happen.
I think expense is basically the problem.
Cost to replace the catalytic converter, cost for new exhaust pipes, cost to diagnose ignition timing problems. Whatever.
If the car drives and you don’t have the money I can completely understand why someone wouldn’t get the problem fixed. Even if it means they’re burning a 1/3 of their fuel, that’s still less in the short term than the $1500 it may cost to fix it.
It’s insanely rare I get the sense that the person is running really dirty on purpose.
I don’t know what a realistic fairway to fix it is. They’re probably isn’t one. I don’t think fines would work, it would probably just make things worse. Seems like the kind of thing where a little government group to find the worst 0.1% of cars on the road and just get them back to reasonable levels would be a huge help.
But that’s not how we do things.
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2005-ish cars were more reliable and had better emissions profiles compared to cars today. Yes cars today are more advanced ,but less reliable, so their emissions overall are worse.
A lot of Americans take their cat off on purpose for louder noises.
Additionally, a lot of conservatives love to "Roll coal", and literally will shit up the environment on purpose just because they feel schadenfreude from pissing of an environmentalist.
> A lot of Americans take their cat off on purpose for louder noises.
Some people remove catalytic converters when they install a performance exhaust. Nobody is doing it for louder noises because the muffler portion is what dampens the sound.
Also I wouldn’t say it’s “a lot of Americans”. We have emissions inspections in most major cities and your car won’t pass if you remove the catalytic converter. They can now detect modified ECUs, too. Someone would have to be so determined to do this that they’d swap the exhaust in and out every time they had to do emissions inspections.
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I’ve run into a few of those. They’re generally pretty obvious. Usually a big truck, lots of MAGA & adjacent bumper stickers.
I haven’t noticed people removing the catalytic converters just for noise. The rare time I see a car that wants to be loud it usually just seems to be the exhaust end they changed, or maybe removed the muffler.
The kind of stuff I’m complaining about mostly seems to be older cars, or those in poor mechanical shape. Cases where the people probably just don’t have the money to fix it.
Besides the crap they pump into the air, they also excrete gunk onto the road. It’s so primitive.
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The exhaust from a well functioning modern ICE is likely enough to have less pollutants than the air. Of course it still has carbon dioxide, but less other pollutants.
you still have tyre rubber, which is a major source of microplastics
And not a distinguishing factor of ICE vehicles
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