I want them to go after muffler shops for noise pollution.
Most states have laws that you can't modify an exhaust to be louder than the stock exhaust.
Yet in every urban area you can hear some percentage of drivers that modify their cars to be 10x louder than everyone else, often with "crackle and pop" tunes to intentionally defeat emissions controls to leave unburnt gasoline to detonate in the exhaust every time they lift off the gas.
It's not just urban areas. It is a scourge that plagues literally every corner of the world. There is nowhere in the city, the suburbs, small towns, or the middle of nowhere where you aren't subject to industrial levels of noise pollution generated by motor vehicles that have been intentionally and illegally modified to make as much noise as possible.
It used to just be motorcycles and sports cars. But it's now the most basic pickup trucks, family sedans, SUVs, and anything else that explodes fuel to move.
The total and complete lack of enforcement of existing noise pollution laws is the number one cause of the spread of this.
I had this problem – near 24/7 noise – but moved 20 miles west to a suburb that has speed bumps and significantly less through traffic. The average dBs outside went from ~65 to ~45. Maybe in the US, at least, the issue is that the quiet urban/suburban places are much more expensive than the loud places and so are relatively inaccessible?
Though, now that I think about it, the depths of New York City will be both very expensive and very loud.
I live in a place that was very similar to what you describe. In the last couple years it's become as bad as where I moved from some days.
A lot of it is the surrounding areas have been surrendered to the noise makers and residents in my town are friends with them and they come and go as they please at all hours, unhindered by law enforcement.
But dismayingly, more of the residents are getting louder themselves for whatever reason. The worst part is they by and large follow the speed limit but are still insanely loud so the police just look at it like I'm just annoyed and need to get over it.
It's truly the easiest thing to catch. I can't fathom why there's so little interest at any level of government to tackle this problem.
The first moves are being made on this. A couple of cities have just started trialing noise detection systems for loud vehicles. I’d like to see this rolled out more, especially in cities where a single asshole on a motorbike can disturb tens of thousands of people in minutes.
What paradise are you in, protecting from noise pollution?
I am in Europe and an opposite problem is that the emission control systems of recent (gasoline) cars are not noise insulated... After you stop a car, it is random artillery for two hours (apparently as they cool down from temperatures of many hundreds degrees).
(Edit: I just replaced 'the opposite problem' with 'an opposite problem'... Former form was misleading.)
I live in the center of an EU capital and there are three main sources of ICE noise:
- motorbikes (with modified exhausts or not, at high speeds the engine itself is loud enough to disturb sleep of thousands of people)
- 'sport' car abominations with intentionally loud exhaust and engine noises
- some diesel cars (old vans etc) are very loud, in this case it's just the nature of the diesel engine.
At least the first two cases should be prosecuted by the police and new vehicles not registered. But never have I seen/heard this level of noise being due to an emission control system, in a stopped car.
Different EU city here, exact same experience. People tune their shitty 25cc motorcycles to sound like a jet engine, people tune their shitty 1200cc cars to sound like a jet engine, and that's 99% of all vehicle-related noise right there.
I live next to a highway on-ramp. The motorcycles are the worst, some of them are so loud while accelerating that it is impossible to have a conversation on my yard, over a hundred meters away.
The city is now investing tens of millions of euros to retrofit a noise barrier to protect our neighborhood. I think our house surfers the most from the noise. Yet - if it only wasn't for those loud motorcycles I would think the noise barrier is unnecessary. It would be much more cost effective to set and enforce noise pollution rules than to build expensive noise protection infrastructure everywhere where people live close to roads.
Reasonably you will lose the discrimination of the "artillery" if you live in a generally loud area - it is not a matter of scalar comparison but of modalities. Place a gasoline vehicle in a parking space and you will hear random bangs from here and there. Bring it to a quiet place, and you will be startled (or worse).
Very unfortunately, yes, I could ;) (...not right now though.)
But look, if you are trying to understand which noise I was referring to: stop some gasoline cars, from euro-5 on, after the engine has been on for a good number of miles, and after a few minutes you will hear like a "loud bang on metal" (very distinct from the usual crackles from the cooling metal), like a coiled spring loudly released, then after more minutes another one... Even after an hour, or more, it will randomly go on... Silent for a long time, then "bang".
I've got an Euro-5 gasoline car and never noticed anything like that, also when driving other/newer cars, and my office window is to a small parking lot, and there also isn't anything like that happening (I am very sensitive to noises). So I think this must me something specific to a car model.
To play the devil's advocate. Not all motorcycle noise is bad. As a car driver, I'm sometimes grateful that I hear bikes before I can see them, they can very easily hide in a blind spot. The way they move through the traffic is in may cases illegal, but I'm not a law enforcement. They drive the way they drive, I can't change that. My primary concern is to not hit them, and some noise on their part helps in that.
From my experience even reasonably priced cars have decent enough noise insulation. Exhaust pipes face back. Inverse square law means the radio has to do very little work to be louder. All this added up you'll only hear the noise terrorist as they're lane splitting next to you.
The US largely doesn't have that. As a German where you got to have your vehicle inspected for code compliance every two years, watching US dashcam videos is completely amazing - some of the shit you're allowed to put on roads there would yield you actual prison time if you tried it in Germany, and not to mention that there are states that do not require a general liability insurance - here it's mandatory to have coverage for at least 7.5 million euros in healthcare, 1.22 million for property damage and 50.000 € for financial loss (say, lost income because the car of the other party is a work car and they need to rent a replacement). Most insurances go above and beyond, standard is like 50 million € of coverage - to hit that, you'd need to crash into a tanker truck on a bridge which then falls down onto a residential home and exploding, or similar sized catastrophes that almost never happen.
Liability insurance for a VW Golf with 15 million € coverage around 160€ a year [1], if you want replacement/weather damage coverage it's about 300-400€. New drivers obviously pay (way) more.
I don't understand how they don't measure exhaust noise levels there! It would at least make it much harder for people to keep the exhaust on if they had to remove it and put it back on for the check.
A lot of manufacturers put in "crackle and pop" as well, on the more sporty models. I guess the catalytic converters etc must be built to handle it, in that case.
It's just a pressure difference, no need for explosions. You can create it with a lean mode as well it's less effective but doesn't kill the muffler and catalytic converter. It's still highly annoying though.
Only effective way to prevent it is a once off "fix it or it get's crushed" notice. And crush it the second time to a tiny tin box.
Thinking more I guess the stock ones are more a kind of "burble on overrun" and maybe a mild anti-lag on shifting (especially on dual clutch models).. thinking of BMW here.
>> Most states have laws that you can't modify an exhaust to be louder than the stock exhaust
Not the big ones. California only limits to 95db, regardless of what stock was. And what is "stock"? Like new? Mufflers start to wear out, getting louder, the moment a car is first started. Not everyone can afford to drive a new car, or even keep replacing the muffler every couple years to maintain some notion of "stock" tailpipe sound. Some of the loudest cars/trucks are simply those old enough to have broken mufflers.
And people with deliberately loud cars want loud cars. If it wasnt mufflers it would be loud sound systems. If not those then it would be loud horns.
A quick primer on what diesel shops are selling with these:
There are 3 main methods of emissions controls on modern diesels
- EGR (Exhaust Gas Return) which takes already burned (hot) exhaust and reinjects it into the intake tract. This causes soot and cokes the intake valves, grid heater, etc.
- DPF (Diesel Particulate Filter) which collects soot until it’s restricted, then burns fuel in the exhaust to cook the soot into ash.
- Catalytic converters & SCR (selective catalytic conversion) which injects corrosive DEF (Diesel Exhaust Fluid/ cow piss) into the exhaust.
If you remove these systems from your vehicle, it won’t run, because the OEMs engine controls say if the DEF tank is empty or it’s throwing codes for EGR or DPF, it won’t get full power.
These shops sell a way to get around that, so you can take all these systems off your engine that kill longevity and efficiency, while not caring about the soot and NOx you’re emitting. A pre-emissions diesel will easily go for 300-400k miles without a rebuild, the modern ones break in really really expensive ways right about the time your warranty ends (60k)
I drive a modern diesel, I race motorcycles and I’ve got a heavy rig to tow to the track, and I’ve left my emissions in place. I don’t love the trade off, it does seem like the manufacturers took the easy way out and tuned their components for timed obsolescence just like the incandescent lightbulb. What these shops are doing is filling a request from owners in states that don’t emissions control these engines, but I guess federally they are breaking the law. Seems grey to me. The manufacturers are only selling the emissions controlled engines to comply with CA and MA and others, while the middle of the country doesn’t control these things.
One thing that is quite important to note is that the EGR is a necessary combustion temperature regulator, and removing it isn’t good for anything, including fuel economy. The engine deposits people blame on it is usually from the PCV.
Only downside to it is that it occasionally need to get cleaned, and in tiny cars it tends to be in a stupid position.
Now, DPF and cats are a bit more black and white, but a bit of horsepower for not giving people lung cancer and worsening the whole environmental situation is an easy trade. It’s ridiculous that it’s not federal as is - stuff that harms everyone around you shouldn’t be your decision.
If one doesn’t like these trade-offs, look into technologies that don’t require them like hydrogen or electric. The trade-offs there tends aren’t as controversial, just personal financial ones like range, weight and charge/fuel supply. And they are getting better.
As an aside, looking at how Edison Motors channel (US company trying to make electric trucks) drools over Scania engines, it seems like US truck engines are quite underpowered yet thirsty compared to the EU. :/
>If one doesn’t like these trade-offs, look into technologies that don’t require them like hydrogen or electric. [...] just personal financial ones like range, weight and charge/fuel supply.
It's not just personal/financial. It's also raw capability of a diesel truck to get the particular type of jobs done.
A lot of the shops did the deletes on trucks that can tow 12000+ lbs. Think of trucks like Ford F-250, F-350, and beyond etc, towing landscaping equipment like a 10000 lb skidsteer on a 14000-lbs-rated trailer. Or hotshot truckers carrying random loads. Some non-commercial trucks (smaller than class 4) can tow up to 40000 lbs.
The Rivian and Cyber trucks only have max tow capacity up to 11000 to 12000 lbs. There isn't a comparable hydrogen/electric substitute that can do what the diesel pickup trucks can do. In contrast, there are realistic EV substitutes for diesel cars.
Those diesel delete shops were typically modifying high-towing-capacity trucks and not the smaller Volkswagon diesel passenger cars. Some truck owners were justifying the deletes because they believe the EGR/DPF/DEF was flawed and would lead to a ticking time bomb of expensive engine repairs down the road. (Cue up a bunch of anecdotes of how the "old diesel engines were reliable and bulletproof" compared to the "new diesel engines with all that EPA emissions crap requiring out-of-warranty repairs" )
I don't know enough about the engineering to know if they're correct or blowing it all out of proportion.
> It's not just personal/financial. It's also raw capability of a diesel truck to get the particular type of jobs done.
What I was saying is not that electric solved all problems yet, but that messing with electric and trade-offs in decisions there only really affect you. Messing with a diesel, the trade-offs affect everyone around you - a bit a power paid by everyone else's cancer risk and deteriorating environment. That's not a decision you should be allowed to make for moral reasons.
With DPF/cat, you do have a risk for expensive service: If you completely neglect it, intentionally run a very sooty tune and never do the (usually automatic) cleaning cycle. At that point, it'll clog up, break, and need to be replaced. But that's easy to avoid, and not something that ups your service interval either. You would also get extremely expensive repairs if you don't change and monitor engine oil, but no trucker would consider it a big deal.
That Rivian only tows 5.5 tons is probably just a matter of demand. Even if it has its uses, I imagine the actual demand for towing 20 tons on personal vehicle is quite low. It could also be that they deemed that the battery range would be too silly at these loads, which is luckily an area of with quite rapid improvement these days - battery range has come a long way.
Also note that you definitely don't need to mess with emissions to tow 20 tons. Messing with EGR grants you zero additional power. Removing DPF and catalytic converter can give you a little bit, but not enough to go from being unable to tow 20 tons to being able, and if you need to tow 20 tons you should start out by buying a truck rated to tow 20 tons as more engine power is not enough to do that safely.
> A lot of the shops did the deletes on trucks that can tow
Don't trust the sales pitch from the tuning shops that sell the mods.
> Cue up a bunch of anecdotes of how the "old diesel engines were reliable and bulletproof"
Heh, those statements are not entirely false, but they forget important details. Some of the engines old-timers might be fondly remembering as indestructible have dual digit HP ratings, at the size and fuel consumption of something rated in the hundreds of HP today.
It's not hard to build an indestructible engine if you don't have to care about size, weight, fuel efficiency, power or responsiveness.
A gas engine could certainly tow my race trailer, but at horrific mpg. I have a gas truck (gets a very nice 22mpg on the highway, which was 2mpg off my wife's RAV4 that seemed like it was powered by hamsters running on a wheel) and towing my trailer it got 3-5mpg. 3 to 5. My diesel gets 12mpg.
EGR "messing with" does affect power. EGR lowers combustion temps, and the thermodynamic work the engine is producing is directly affected by the temperature gradient between the combustion chamber and the outside air. Lower temp == lower efficiency. Does cut down on NOx, but let's at least be honest about the negatives.
My point is more like this: EGR seems to help with two things, 1. fixes the NOx problem (ok that is legitimate) 2. Injects soot into the engine's intake, covering everything in coke, but at a slow enough rate that they don't fail during the warranty period. Helps with planned obsolescence, considering how everything is made cheaper and crappier now, on purpose so you have to throw it away and buy a new one, no one is going to convince me that #2 isn't a net positive to the OEMs, and it also giving them a darn good reason not to search for other methods to reduce NOx emissions in a way that doesn't help the engines expire more quickly.
Like I said, I did not delete my truck, nor would I. I care about the environment and the air we all breathe. But I don't buy that there aren't other ways to solve these issues.
> A gas engine could certainly tow my race trailer, but at horrific mpg
Gasoline engines actually have their highest fuel-to-power efficiency at full throttle. A more powerful engine just allows you to burn even more fuel to accelerate faster.
I suspect that the gas trucks gear ratios just made it unsuitable for towing by putting you way outside the optimum power band at load. This is why I said that power is not the only factor: You need a chassis, brakes, gear ratios and possibly transmission cooling for suited for towing that heavy loads. I stretched a chassis once towing way over the rating - I recommend not doing that.
22 MPG is also pretty bad by today's standards, but I've had engines like that. At 12mpg you're getting very close to the fuel consumption of the compact 48 ton trucks we use in the EU, but they usually have almost 800 HP under the... seat.
> EGR "messing with" does affect power. EGR lowers combustion temps .. but let's at least be honest about the negatives.
Temporarily, at idle, it does lower efficiency yes. But it's during the phase of engine operation with the lowest possible fuel consumption, and while all the fuel you're burning is thrown out the window. It is also only fully open in a very specific scenario, and otherwise at idle or very low power demand it will only be slightly open.
I don't think the cooled cylinder is harmful - it would eventually cool that that temperature at idle even without the EGR, and a hot cylinder preheats gasses on the way in, reducing the possible temperature gradient.
> But I don't buy that there aren't other ways to solve these issues.
As mentioned in a different comment, the EGR efficiency concern is entirely gone with engine start-stop as the time when it would be fully open is replaced by the engine being off. That improves fuel consumption past a deleted truck.
I agree that emissions-related tech is a hack in many ways, but the problem is that internal combustion engines are terrible and hard to fix. For most people, electric already works fine, and most complaining about spec comparisons never need those specs.
For others, older technology will stick around for a bit longer until we have mature solutions. Plus, if all regular cars and trucks get replaced by something better, having a few (properly emissions controlled) gas trucks on the road won't matter as much.
I've seen far less reports of soot and smog in recent years (though it's still there), and it's the same with vaccines: People don't remember how bad it was and then argue against the thing preventing it. Also: smog and soot deposits don't care about state borders.
> EGR is a necessary [...], and removing it isn’t good for anything
EGR is what killed responsiveness in internal combustion engines. I'm not advocating breaking the law, but it would be nice if people remembered what we are missing and started pushing for having it back.
I don't see how the EGR could possibly affect perceived responsiveness. What "killed responsiveness" in my opinion is heavy turbocharging with long spool-up times, with engines so small that they cannot even maintain highway speeds at full throttle without boost pressure. Or, if only naturally aspirated engines are responsive enough for you, boost altogether.
The EGR only opens when the cylinders are running too hot and there is is no request for power. It is fully closed during normal driving, and even when it is open it will slam shut the moment you touch the throttle. Heck, you might not even experience it opening at all during some driving sessions.
> but it would be nice if people remembered what we are missing and started pushing for having it back.
We got something far, far more responsive: Electric. Combustion engine don't even make it to the leader board, and with some of the electric options out there, the speed of your throttle foot ends up being a significant bottleneck.
Did you watch that video you recommended? Might need a rewatch.
1. My diesel, like most now is a turbo. Pumping losses are not relevant.
2. 30% lower combustion temp relates to that level of efficiency loss
3. The EGR is open A LOT to keep NOx down from a modern diesel.
3. The COMBO of PCV and all the soot from EGR is the exact problem. The oil from PCV wouldn’t coke in the intake tract without the soot, its oil mist. You pop open an engine with PCV and no EGR and the intake tracts are a little oily. Open a diesel with EGR and you see what it looks like in that video.
Regarding electric, what’s the range of the available electric tow vehicle that costs 50k and can tow 18,000 lbs with 10% of that on the rear axle? -inf because it doesn’t exist.
I had an electric car, I’m all for it for single vehicle travel. For actual towing, like I use my truck for, it’s going to take a step change in battery capacity. I would welcome a heavy hybrid in the style of modern trains, I’ll spend more than I make up in fuel economy to purchase it.
Yes, I did. But I feel like you missed key points?
1. The video mentions pumping losses because it was an old argument against EGR, which only applied to older diesels relying on a butterfly valve for vacuum. Pumping losses still matter in a turbodiesel though, as it's a resistance you need to overcome with more fuel.
2. At idle, when the EGR is open, you get a lower combustion temperature which accelerates the natural cooling of the combustion chamber that happens at idle. So at that point, when the engine is using the least possible amount of fuel, efficiency will be dropped for a while.
But:
3. The EGR is only ever fully open for a bit when idling after the cylinders have been run hot. Once the temperature has dropped a bit, it will be only be slightly open. When you press the gas, it closes entirely. When fully closed, it has no impact on efficiency.
4. No, the EGR is entirely harmless - the small amount of recirculated exhaust gas only contains things that were already present in the cylinder a moment ago. The PCV on the other hand pulls oil into the combustion chamber.
If you're concerned about the idle fuel economy impact of the EGR, get a car/truck with start-stop as it removes the concern entirely, netting you an inf% improvement to idle fuel consumption.
> Regarding electric, what’s the range of the available electric tow vehicle that costs 50k and can tow 18,000 lbs with 10% of that on the rear axle? -inf because it doesn’t exist.
Ignoring that it wouldn't be "minus infinity", no one is claiming that someone actively towing 18000 lbs should buy an electric before they can do what you need them to do.
People can get over-excited about technology to the point of pushing it a bit too hard. If you have an actual need (most people citing towing capabilities have never used their trailer hitch), keep using a gasoline truck with the correct factory emission equipment until the better technologies have matured for your use-case.
One YouTube video does not make you an expert. I’m a mechanical engineer and I’ve been building and running these my whole life, but if my creds don’t work for you, check out Gale Banks or Dave’s Diesel, a couple of shops that don’t sell delete kits but will explain the obvious thermo, physics, and design issues with what I’m telling you is a problem, then explain why.
EGR only open for a bit when the combustion temp is high. Good god. What are you even talking about. You couldn’t be more wrong if you tried to be.
Pumping loss doesn’t matter to a turbo. Are you familiar with a wastegate?
EGR LOWERS COMBUSTION TEMP. Engine efficiency is directly correlated with the temp gradient between the combustion temp and the outside air. By the way each cycle is its own thing. Conductive or radiant heat from the last cycle is so insignificant you ignore it in the calculations. The barrier layer insulates the charge from the cyl wall and piston temps or you’d melt everything in the engine first time it fired.
You should take some college level thermo courses before you start popping off like an armchair expert. At least figure out what you don’t know before you just add another data point to the corpus trying to make sure dunning Kruger effect is actually backed up by examples.
EGR is not required to control combustion temp. I’ve been building motors and competing in Motorsport all my life, never used EGR and my temps are great.
It’s for emissions and on a diesel, injects soot into the intake
It injects a small amount of gas that came from the cylinder back into the cylinder - nothing that doesn't belong in a cylinder. The only source of extra gunk and buildup is the oil droplets or outright drooling pulled in by the PCV.
The reason you never used an EGR is because you're building for motorsport - you don't care that your cylinders are too hot for too long when you release the throttle. You care about what happens at or near peak power, and even if you had an EGR it would be fully closed, so why bother.
Note that it's for any combustion engine, not just diesel.
It injects exhaust. Burned fuel air with NOx, CO, CO2, and very little oxygen. It does this to lower in cylinder combustion temp and reduce the formation of NOx. Less oxygen in the cylinder means less temp which means less power. That is just a fact, it’s thermodynamic law, you literally can’t dispute it.
The only Motorsport engines built for full throttle only are drag and pull engines, but where I race throttle response and the whole torque curve from 8,000 to 16,500 RPM is incredibly important. Find me an EGR system on any purpose built engine that didn’t have to comply with emissions. Industrial engines, race engines, tractors, generators… anything. That should illuminate what EGR is actually for.
> If one doesn’t like these trade-offs, look into technologies that don’t require them like hydrogen or electric. The trade-offs there tends aren’t as controversial, just personal financial ones like range, weight and charge/fuel supply. And they are getting better.
Yeah, I think the attempts to do "clean" diesel are doomed. Volkswagen proved that the standards couldn't be met without cheating. The EU petrol/diesel car phaseout starts in 2035, but perhaps the diesel side of the phaseout needs to be more aggressive such as rationing the number of diesels sold or putting more "low emission zones" in place.
The push for diesel was also... Weird. It was a way of dealing with a supply chain issues, whereby a demand of heavier oil was needed for production to stay economical.
I work at a b2b diesel vehicle oem and our vehicles routinely do in excess of 130k miles per year. The first owners usually keep them for 3-5 years before selling them. They don't, generally, require rebuilds for the first few owners.
If you're experiencing that sort of issue, it is not specifically because of the emissions devices. It's because of poor design or cheap parts.
Pretty well understood in the community that drives consumer diesel vehicles (Ford, Ram, GM) that the main failure modes are emissions systems (or the CP4 pump) The costs are astronomical as well. $7k for a DPF. What vehicles are you selling that aren't seeing issues?
Tampering/defeating emissions systems isn't a grey area. Anyone can likely get away with it in the same way they can get away with dumping all kinds of pollutants into the air/water/soil.
The federal government also regulates nox, ppm, etc...
CARB has more stringent regulations, but I believe most of the companies selling defeat devices are removing the emissions components, not tuning a truck that complies with 2024 CARB standards to instead comply with 2024 federal standards.
I think anything built before 1970, or whatever the specific year is, can be legally modified however you want. It's just not legal to take something newer and remove some/all the emissions equipment
IF companies wanted to make vehicles that complied with the diesel emissions requirements of say Michigan, they could make a fully unrestricted diesel. The federal government buys Fords with diesel engines with factory EGR block off plates and no DPF for example. Do as I say, not as I do.
Consumer diesel engines had no controls up to around 1999 I think
Of course they could, but they won't because it breaks federal law.
Tactical/emergency/etc vehicles can be exempted from federal and state emissions for obvious reasons, but most federal vehicles are not exempt.
> Contrary to past practices, vehicles owned and operated by the Federal government are not automatically exempt from having to under emissions testing and obtains proof of that testing. Some states, in their state regulations exempt classes of Federal motor vehicles, usually those for tactical use.
> - Catalytic converters & SCR (selective catalytic conversion) which injects corrosive DEF (Diesel Exhaust Fluid/ cow piss) into the exhaust.
DEF is urea, yes, but that urea doesn't come from piss, it's synthetic - urea production was the first synthesis of an organic compound in fact, made possible at scale after the Haber-Bosch process was invented that produced the precursor ammonia.
> the modern ones break in really really expensive ways right about the time your warranty ends (60k)
bullshit, common rail turbodiesels with EGR+DPF have been around for decades. they had some issues at the start (like all new tech) but now the longevity is similar to modern turbo petrols
I'm regularly involved in the car community, and this is far more common than is often thought. I've met dozens of people who have illegally modified their diesels, and that's in California. There's plenty more for the EPA to crack down on.
Car modders toss catalytic converters all the time too in states without emissions enforcement. It's just not a problem that is handled.
At one point I was working on a startup idea that would produce a piece of electronics for helping with drive train swaps. However, I realized that it would make it very easy to ignore all emission and safety requirements despite my efforts to prevent that. So I dropped the entire idea and moved on with my life. I don't want to unintentionally help other people make the planet worse.(But I also wanted people to reuse/recycle car parts more effectively. Oh well.)
What do these "emissions defeat" devices do? Are they to make the engine produce more power, or to be able to pass emissions testing (like how VW try to make their cars seem less poluting by detecting whether or not the engine was under test and altering engine behavior)?
They might turn off/block egr which reintroduces exhaust gasses to intake to reduce combustion temperature. The upside of this system is that it reduces NOx emissions, the downside is that you’re bringing a lot of soot inside the engine. They are abrasive.
Combine egr with pcv, which directs positive crankcase pressure into the intake, you get an oily sooty mixture caking inside the intake.
Combine this with swirl flaps, which create a small tornado at lower engine speeds for better combustion, you get caking on the flaps and your intake becomes halfway clogged.
These are my annoyances. But to be honest, it didn’t require cleaning even after 250.000 kilometers of driving. I saw the caking while doing some other work, but the engine was running fine
But there’s also the dpf, and the adblue stuff. Dpf is an issue only if you use wrong kind of oil and clog it. I’m assuming people remove the dpf to run coal, as it will get clogged extremely fast if you detune your engine. It might also be an annoyance if you want to mod the engine, but not sure on that front. And adblue is yet another thing to fill every now and then. No experience with that, but I assume it might annoy some.
When you start "rolling coal" all the "gains" by removing the EGR and PCV will be negated since you will be lining your valves with tar and ruining the oil.
Diesel engines tend to be larger/bigger/heavier than petrol engines due to higher compression/pressure inside. They warm slower. Cold engine needs a rich mixture and that causes polution with unburnt fuel (mostly carbon). These devices are designed to filter that.
The downside is that engines used for short trips at low power (city driving) rarely get to high enough temperature to burn the carbon in the filters. Filters/catalytic converters get clogged and cause engine warnings / errors and bad performance.
Depends on what the owner wants. The ones that are rolling coal are removing all the filters then deliberately running their engine rich. The black smoke is literally unburnt diesel. Obviously when you're spraying huge clouds of diesel, your fuel efficiency is going to go down.
After Dieselgate, Volkswagen brought their diesels into compliance by software patch. People did dyno runs of all VWs before and after the patch, and in many cases (e.g. the 180HP Passat) got something like 10% less horsepower and drastically worse torque curves (max torque at 1900 rpm instead of at 1500 rpm) after the patch. Fuel economy also went down by around 10% because of the patch.
Makes sense from a thermodynamic perspective: your engine runs with more power/torque and more efficient if you run it hotter. But running a diesel hotter makes much more NOx.
Some parts of the emissions control systems (I was informed by competent technicians, but not yet adequately "educated") work through burning extra gasoline and fuel - they are active, they use energy.
The extra intake may seem pretty dramatic - though of course full data for comparison should be in order... It should be possible to compare euro-4 vs euro-5 model consumption through spritmonitor.de (through selecting by year) - I have no time right now but may do it later, and possibly report.
Multiple things. EGR, the scr, and particulate filters are not super reliable, and when they fail, either your truck goes into limp mode or if your EGR cooler failed and your engine sucked in coolant, you're buying a new engine. They also give you slightly better fuel economy and more torque/horsepower.
Then there's the real jackasses (like my cousins) that delete all that stuff along with the muffler and deliberately blow clouds of black smoke because deep down they are deeply insecure people and suffer from undiagnosed depression and anxiety.
Given that diesels emit particulates and nox as well as co2, I'll note it's theoretically possible to tune them in a way that increases efficiency at the cost of other pollutants. I've no idea what the actual devices sold do, though.
They made 33M and were fined 9M? Roughly a net profit of 24 Million? Yes I'm sure they totally learned their lesson and would never make tens of millions in defiance of lax enforcement again.
Most states have laws that you can't modify an exhaust to be louder than the stock exhaust.
Yet in every urban area you can hear some percentage of drivers that modify their cars to be 10x louder than everyone else, often with "crackle and pop" tunes to intentionally defeat emissions controls to leave unburnt gasoline to detonate in the exhaust every time they lift off the gas.