This is the unfortunate effect of direct injection engines with EGR (Exhaust Gas Recirculation). This video shows you how bad it can be. I have seen worse. Unfortunately it dose need to be cleaned manually and preventative work needs to be done as explained by Max. Max thank you for pointing out to your viewers the sneaky hidden bolt. 🙌
Thanks for your comments. As I mentioned in the comments, the EGR is involved with the carbon build up, but not the creation of it. Many turn to EGR delete as an option, but as I have mentioned in other comments, as it is illegal, I do not consider it an option. Yes, I also have seen worse, this just happens to be the one that I did a video on. There is no real way to get the carbon out without creating other issues on the way out the exhaust system - manual cleaning must be done. Then preventive maintenance can be done after with chemicals to try and keep it clean. I knew this would be a hot topic! Everyone has thoughts on the matter. I can only go on what I have personally experienced over the years dealing with this issue. Thanks again for your comments. 👍😉
Yes, this is very controversial, but the gasses themselves are created by the combustion process, via the PCV system. The EGR just makes the problem worse by recirculating the gasses to lower combustion temperature and lower NoX levels. Thanks for your comment. 👍
JFYI - graphite (carbon powder) is a lubricant.. The problem are chunks of it getting dislodged and blocking valves from closing correctly, not to speak of the oily-soot-smoke that's coming out of the crank-case (caused by blow-by) which is being put into the air-intake of the engine (in my case, Mitsubishi Triton MN, 2.5DiD 4D56U engine) right before the turbo charger - which is being mixed with the EGR-gas right before the manifold, which then really builds up and blocks the intakes. Catch can's should (in theory) catch most of the oily-soot.
@MiracleMAX i understand, we use hho cells aswell , family has used them for nearly 50 years , they keep the combustion chamber , exhaust very clean , even if you just put a few hundred mls of gas per min into the air box. low amounts dont mess with the O2. they make a big difference on deisels, always amazed me on old school deisels how much cleaner the exhaust was even under load zero smoke, and very low nox, freind is a retired mechanical engineer he tested his old vw beetle , without the cell switched on his omissions were terrible , with the cell switched on the omissions were so low it amazed the guys , it was lower than a modern car. but youve got to do it right and safe using safety devices etc. im not sorry using them all these years.
I drive a TDI ALH in North America and owned it for 20 years. I've had to spend thousands of dollars to get my intake manifold cleaned (four times). I'm going to try to do it myself for the first time and save some $$$. When I do it I will be doing an "EGR delete" but not really delete the EGR, just the hot air cooler so no recirculated exhaust is going back in.
EGR gas is EXPECTED by the ECU and proper function of the engine.. if u 'delete' it the ECU program needs to be adjusted to account for this, otherwise u can destroy ur engine.
@@joansparky4439 my exhaust gas cooler looked pretty clogged up with carbon so I don’t thing anything was getting through. What is more, it’s a common delete on TDI ALH and I haven’t read about any damage.
100% best way to clean is pull apart ,i found oven cleaner and a pressure washer but im hundreds of km from a acid tank to send it in, good vid nice job
Yes you are correct. I have heard of oven cleaner being used, although I've never done it myself. Removal and cleaning is the only way to remove the carbon safely. 👍
Hi Max, you want see wet carbon, wait till you have to Hyundai i40, I took the intake of to clean and couldn't even see the swirl flaps and the were stuck, I eventually cleaned enough to see the flaps only to find two missing, the are made of plastic. All cleaned and back together, 8 hours from start to finish and ordered another intake and another 6 hours. Bought a small catch can from Western Filters and no room in the engine bay, after making a few brackets and some modifications to the engine cover it fitted. Drained twice a week and has a very thick sludge. What chemical do put in your Ultrasonic Cleaner? I have just started to use Simple Green Multi Cleaner, big parts go into a plastic bag with the solution and taped up up with electrical tape (small parts in a zip bag) and into the water of the ultrasonic cleaner, this way I only have a small amount of chemical to dispose off and the water stays clean in the ultrasonic cleaner. Thanks for posting, I will be cleaning the intake every 50k.
Great to hear from you Rich. Not unusual to see swirl flaps break or disappear. A bit scary to think of where they go! Depending on how bad they are, some just quote on a new manifold as it works out cheaper than replacing the swirl flaps and cleaning it. I just used CT-18. You can use an 'official' ultrasonic cleaner, but it gets pretty pricey. I use oven bags for some parts - it copes with the heat OK. It's a good idea to keep the water clean. To be honest, I forgot in this case. 🤦♂️ Regular preventive maintenance is the only answer. Hopefully the catch can will help with the process. Thanks for your comments
Beware those catch cans with paper filter, they can cause pressure build up in the crankcase causing oil leaks past the seals. I've seen several cars getting multiple rear main seals fitted and still leaking
EGR would give just a dusting of soot. PCV just gives a film of oil. Add them both together and we have a vegemite mess. Manufacturers only have to clean up one or the other and there won't be such a big problem, but it is only a problem outside of the warranty period.
Great video Max and very informative. I was quite interested in this as I have a NX with the same motor 3.2 L. I fitted a pro vent catch can at around 75000km and it certainly catches quite a bit of oil out of the blow by gases. You mentioned near the end of the video about small injection quantity relearn. I would be very interested how this is done so maybe in the future if you could do a video on this that would be great.
Hi max, I would have liked to see a comparison for driveability before and after, or even a dyno test pre and post. Im a mechanic too, and the inlet on my diesel is way worse than what you show in this vid. It would be cheaper for me to replace the inlet man entirely, however my car still has a ton of power and excellent economy. Catch cans can help, but do void warranties.
I agree. I would have liked to do a comparison, however, the customer made comment that they noticed an increase in power, fuel economy and ease of starting. All without any input from me. I'm sure different engines would respond differently due to many different factors. I agree, some do decide to replace the manifold. Some also have a clean one in stock to change over to save time and then clean the other, ready for use on another engine. Thanks for your comment. 👍😉
Apropos 'preventative maintenance'.. how is this going to work out vis-a-vis the common-rail-injector lines (200 bar I think) and their finite tighten-loosen-cycles? On the Mitsubishi 4D56U engine this limit is at 7 cycles, then they have to be replaced - and they are costly (for what they are).
Mitsubishi recommend injector pipes need to be replaced every 6 times. It's in the owners service book that we stamp. Keep in mind, they need to come off to do the valve clearances, so that is an ideal time to do a carbon clean. That way you are only replacing the pipes when you would normally do them for the valve clearance adjustments. That is the customers cost stipulated by Mitsubishi. Sure cheaper than a fuel leak under the rocker cover into the engine.
Have a LF1 3 0L SIDI VE would a sonic cleaner with a probe work for inside valve ports with heads on ? also getting a coating of dry soot on the plugs could this be the pcv do I need a catch can on it as well?
The best option for inside the head is the use of a walnut blasting medium. The soot on the spark plugs could be a range of issues depending on how much there is. Catch cans can also be installed on petrol engines.
@@theaussie7160 We used to use these when I installed LPG systems to help with valve recession. I believe this would probably make the carbon issue even worse as it adds an oil additive into the intake system.
But then the emissions would run untreated out to the atmosphere. Unfortunately, even if it did work, it would be illegal. Thanks for thinking outside of the box.
Sorry Max but what about the actual head? I have seen a device which covers the inlet and smashes walnut shells into and immediately sucks them out of the head.
Yes, you are correct. That would be the best option. I did mention it in the video description as well as in the video itself. th-cam.com/video/OuR3-TU1cXg/w-d-xo.html Unfortunately I don't have that unit. I have seen them made, including using a shop vacuum to remove the waste. Next on the tool list......
Seen one so tightly blocked that it only be tow started and will only just make idle speed but excelerater flat after clean out ,, wow economy power you name it ,, it was a new car again, good for 100,000km then repeat process,, this is Mitsubishi
Remove and refit dpf for roadworthy every yr only leave it on for the hour or so it takes for check engine will last five times longer and you wont have to replace dpf ever
Your explanation of where the carbon comes from is wrong. It does not come only from blowby, most of it comes from EGR feeding diesel exhaust back into the intake, where the oil mist blowby mixes with it and forms the sludge. It's why we block off the EGR when possible, and fit a catch can to condense as much of the misty blowby to reduce the oil in the inlet tract.
The EGR system does not create the carbon, as I have explained before. It does however recirculate the gases that makes the situation worse. As I did in the video, installing a catch can is able to help with the problem. I have also stated that an EGR delete is not legal and therefore I do not recommend it.
@@MiracleMAX The EGR system DOES create the problem, because older diesel engines without an EGR system but with a PCV system do not clog up the inlet manifolds with carbon. The carbon is the black soot you see coming out of old diesels with no filters, so pumping that soot into the inlet and mixing with oil mist from blowby is exactly where the buildup comes from. It's also why diesels are far worse than petrols in this regard, because petrol EGR does not have the diesel soot.
@@einfelder8262 I'm not doubting that. But, the carbon is created by the combustion process. Previously, fuel used to pass the intake valves and help 'wash' them. With direct injection, only air is taken into the intake system - fuel is added in the cylinder. No 'washing' of the intake system takes place. Yes you are right, diesels are far worse than GDI. I appreciate your view on the matter. Thanks for your comment
@@MiracleMAXYou're missing the point. The combusted crankcase ventilation gases are directed from the crankcase to the air intake pipe, usually before the turbo. This oily mist travels with the fresh air to the inlet manifold. This is where it meets and mixes with the sooty, carbon filled EGR exhaust gas and forms the oily carbon sludge. There's two ways to avoid this. Either install an oil catch can and vent the remaining CCV gas into the atmosphere so only dry EGR gases enter the inlet manifold or the most preferred method is to block the EGR so only the oily mist enters the inlet manifold and burns up in the combustion chamber. I've actually managed to clean my valve stems of carbon (direct injection diesel) over a period of six months by blocking my EGR as the oily mist rushing through the inlet manifold venturis broke down the carbon on them. Obviously this isn't powerful enough to clean the chamber of the inlet manifold. I noticed the shiny valve stems when I removed the clogged inlet manifold. I soaked it in a diesel bath overnight. Pulled it out in the morning and all the sludge just fell out of it.
If you just blank off the egr all if this mess is gone and your oil keeps way cleaner for more kilometers. We all know this got nothing to do with regular oil change. the egr is the main component for this problem.
The carbon is created by the combustion process. The EGR recirculates some of those gasses to lower the NoX gasses due to temperature changes. To blank off the EGR is not legal, therefore I can not recommend it.
I guess manufacturers are required to fill emission requirements as stated by law to care for the environment. Emission levels have dropped due to these features - love them or hate them.
This is the unfortunate effect of direct injection engines with EGR (Exhaust Gas Recirculation). This video shows you how bad it can be. I have seen worse. Unfortunately it dose need to be cleaned manually and preventative work needs to be done as explained by Max. Max thank you for pointing out to your viewers the sneaky hidden bolt. 🙌
Thanks for your comments. As I mentioned in the comments, the EGR is involved with the carbon build up, but not the creation of it. Many turn to EGR delete as an option, but as I have mentioned in other comments, as it is illegal, I do not consider it an option.
Yes, I also have seen worse, this just happens to be the one that I did a video on. There is no real way to get the carbon out without creating other issues on the way out the exhaust system - manual cleaning must be done. Then preventive maintenance can be done after with chemicals to try and keep it clean.
I knew this would be a hot topic! Everyone has thoughts on the matter.
I can only go on what I have personally experienced over the years dealing with this issue.
Thanks again for your comments. 👍😉
It's not the crank case venting that causes this, its the EGR. Good explanation on how to get the parts off.
Yes, this is very controversial, but the gasses themselves are created by the combustion process, via the PCV system. The EGR just makes the problem worse by recirculating the gasses to lower combustion temperature and lower NoX levels.
Thanks for your comment. 👍
It's both mixing when they meet in the inlet manifold.
JFYI - graphite (carbon powder) is a lubricant..
The problem are chunks of it getting dislodged and blocking valves from closing correctly, not to speak of the oily-soot-smoke that's coming out of the crank-case (caused by blow-by) which is being put into the air-intake of the engine (in my case, Mitsubishi Triton MN, 2.5DiD 4D56U engine) right before the turbo charger - which is being mixed with the EGR-gas right before the manifold, which then really builds up and blocks the intakes. Catch can's should (in theory) catch most of the oily-soot.
That's a great explanation of the problem, thanks for sharing!
many years ago we put a catch can and egr delete , no issues since
There are solutions, but as I said before, I can only suggest legal ones.
@MiracleMAX i understand, we use hho cells aswell , family has used them for nearly 50 years , they keep the combustion chamber , exhaust very clean , even if you just put a few hundred mls of gas per min into the air box.
low amounts dont mess with the O2.
they make a big difference on deisels, always amazed me on old school deisels how much cleaner the exhaust was even under load zero smoke, and very low nox, freind is a retired mechanical engineer he tested his old vw beetle , without the cell switched on his omissions were terrible , with the cell switched on the omissions were so low it amazed the guys , it was lower than a modern car.
but youve got to do it right and safe using safety devices etc.
im not sorry using them all these years.
@closertothetruth9209 Interesting, good to know
Hi Max. Great video, but you didn't discuss why it happens - Exhaust Gas Recirculation. And what the owners options are to stop it happening "proper"
I did list that as a cause in the comments. It is not legal to do a delete, so I don't list it as an option.
I drive a TDI ALH in North America and owned it for 20 years. I've had to spend thousands of dollars to get my intake manifold cleaned (four times). I'm going to try to do it myself for the first time and save some $$$. When I do it I will be doing an "EGR delete" but not really delete the EGR, just the hot air cooler so no recirculated exhaust is going back in.
I hope it goes well for you
@@MiracleMAXHow much can a procedure like this cost $$$???
EGR gas is EXPECTED by the ECU and proper function of the engine.. if u 'delete' it the ECU program needs to be adjusted to account for this, otherwise u can destroy ur engine.
@joansparky4439 Well put!
@@joansparky4439 my exhaust gas cooler looked pretty clogged up with carbon so I don’t thing anything was getting through. What is more, it’s a common delete on TDI ALH and I haven’t read about any damage.
Great video with excellent advice Max, including a bit of comedy in the mix 😁👌🚘🚗
Thanks mate! I appreciate your feedback.
100% best way to clean is pull apart ,i found oven cleaner and a pressure washer but im hundreds of km from a acid tank to send it in, good vid nice job
Yes you are correct. I have heard of oven cleaner being used, although I've never done it myself. Removal and cleaning is the only way to remove the carbon safely. 👍
Very well explained. 😊 . It's a JOB I have to do soon .
Have fun! 🤔
Hi Max, you want see wet carbon, wait till you have to Hyundai i40, I took the intake of to clean and couldn't even see the swirl flaps and the were stuck, I eventually cleaned enough to see the flaps only to find two missing, the are made of plastic. All cleaned and back together, 8 hours from start to finish and ordered another intake and another 6 hours. Bought a small catch can from Western Filters and no room in the engine bay, after making a few brackets and some modifications to the engine cover it fitted. Drained twice a week and has a very thick sludge.
What chemical do put in your Ultrasonic Cleaner? I have just started to use Simple Green Multi Cleaner, big parts go into a plastic bag with the solution and taped up up with electrical tape (small parts in a zip bag) and into the water of the ultrasonic cleaner, this way I only have a small amount of chemical to dispose off and the water stays clean in the ultrasonic cleaner.
Thanks for posting, I will be cleaning the intake every 50k.
Great to hear from you Rich.
Not unusual to see swirl flaps break or disappear. A bit scary to think of where they go!
Depending on how bad they are, some just quote on a new manifold as it works out cheaper than replacing the swirl flaps and cleaning it.
I just used CT-18. You can use an 'official' ultrasonic cleaner, but it gets pretty pricey. I use oven bags for some parts - it copes with the heat OK. It's a good idea to keep the water clean. To be honest, I forgot in this case. 🤦♂️
Regular preventive maintenance is the only answer.
Hopefully the catch can will help with the process.
Thanks for your comments
@@MiracleMAX Just out of interest sake , what size ultrasound do you have / find works?
@@rossbeck1595 I use a 30 Lt tank
@@MiracleMAX Thankyou
Excellent work as always mate, horrible stuff isn't it 😶 I can feel the carbon on my skin just watching this 🤣
Tell me about it! You have to spend a week in the shower with a scrubbing brush to get back to normal! 😉🤦♂️
On ya Mad Max. Another top notch video.
Thanks heaps! 😊👍
Beware those catch cans with paper filter, they can cause pressure build up in the crankcase causing oil leaks past the seals. I've seen several cars getting multiple rear main seals fitted and still leaking
Good advice! You get what you pay for. I've also heard of people connecting the hoses backwards which creates all sorts of havoc
How much labours would you charge for that particular job
Depends on the vehicle and how much carbon build up there is.
Would a good quality catch can help
Yes, that's what I stated in the video. th-cam.com/video/OuR3-TU1cXg/w-d-xo.html
EGR would give just a dusting of soot. PCV just gives a film of oil. Add them both together and we have a vegemite mess. Manufacturers only have to clean up one or the other and there won't be such a big problem, but it is only a problem outside of the warranty period.
Yes, it makes a real mess. Some manufacturers use other strategies instead of an EGR system
Great video Max and very informative. I was quite interested in this as I have a NX with the same motor 3.2 L.
I fitted a pro vent catch can at around 75000km and it certainly catches quite a bit of oil out of the blow by gases.
You mentioned near the end of the video about small injection quantity relearn.
I would be very interested how this is done so maybe in the future if you could do a video on this that would be great.
Thanks for your comment.
I have already done a video on the relearn procedure. Here's the link:
th-cam.com/video/Z6_ru3XxO20/w-d-xo.html
Thankyou that's great 👍
Hi Max, very informative video. I was just wondering what the kilometres were on that Mitsubishi.
217,544 Km. I just checked the invoice. 👍
Hi max,
I would have liked to see a comparison for driveability before and after, or even a dyno test pre and post. Im a mechanic too, and the inlet on my diesel is way worse than what you show in this vid. It would be cheaper for me to replace the inlet man entirely, however my car still has a ton of power and excellent economy. Catch cans can help, but do void warranties.
I agree. I would have liked to do a comparison, however, the customer made comment that they noticed an increase in power, fuel economy and ease of starting. All without any input from me. I'm sure different engines would respond differently due to many different factors.
I agree, some do decide to replace the manifold. Some also have a clean one in stock to change over to save time and then clean the other, ready for use on another engine.
Thanks for your comment. 👍😉
I would like to see the inlet manifold of a common rail diesel fitted with a catch can after 100,000kms
Yes, that would be good, but there are so many variables that it would be hard to predict
Very informative video. What solution did you use in the ultrasonic cleaner? Thank you
You can buy ultrasonic cleaning solution, but that gets expensive. I use CT18 Superwash. It seems to work quite well.
Apropos 'preventative maintenance'.. how is this going to work out vis-a-vis the common-rail-injector lines (200 bar I think) and their finite tighten-loosen-cycles?
On the Mitsubishi 4D56U engine this limit is at 7 cycles, then they have to be replaced - and they are costly (for what they are).
Mitsubishi recommend injector pipes need to be replaced every 6 times. It's in the owners service book that we stamp. Keep in mind, they need to come off to do the valve clearances, so that is an ideal time to do a carbon clean. That way you are only replacing the pipes when you would normally do them for the valve clearance adjustments. That is the customers cost stipulated by Mitsubishi. Sure cheaper than a fuel leak under the rocker cover into the engine.
Have a LF1 3 0L SIDI VE would a sonic cleaner with a probe work for inside valve ports with heads on ? also getting a coating of dry soot on the plugs could this be the pcv do I need a catch can on it as well?
The best option for inside the head is the use of a walnut blasting medium. The soot on the spark plugs could be a range of issues depending on how much there is. Catch cans can also be installed on petrol engines.
Would a Flashlube electronic valve saver kit be a good idea for carbon build up prevention on direct injection
@@theaussie7160 We used to use these when I installed LPG systems to help with valve recession. I believe this would probably make the carbon issue even worse as it adds an oil additive into the intake system.
You did a good job. Theoretically 😉 you could perhaps, run that PVC line to a bung on the exhaust pipe.
But then the emissions would run untreated out to the atmosphere. Unfortunately, even if it did work, it would be illegal.
Thanks for thinking outside of the box.
Sorry Max but what about the actual head? I have seen a device which covers the inlet and smashes walnut shells into and immediately sucks them out of the head.
Yes, you are correct. That would be the best option.
I did mention it in the video description as well as in the video itself.
th-cam.com/video/OuR3-TU1cXg/w-d-xo.html
Unfortunately I don't have that unit. I have seen them made, including using a shop vacuum to remove the waste.
Next on the tool list......
Is pajero only victim, seen many of them done now
Many Common Rail as well as GDI engines suffer the same fate
Yes Subaru cleaner ,, good shit used before on carby on Honda mowers and motorcycles when petrol gums them up
Vile smelling stuff, but it sure does work!
Seen one so tightly blocked that it only be tow started and will only just make idle speed but excelerater flat after clean out ,, wow economy power you name it ,, it was a new car again, good for 100,000km then repeat process,, this is Mitsubishi
Yes Carbon is a real killer
Best remedy for this in a diesel was EGR fix and putting water methanol injection 😂 and on petrol just getting a port injected car 🤣
Good to know
Remove and refit dpf for roadworthy every yr only leave it on for the hour or so it takes for check engine will last five times longer and you wont have to replace dpf ever
There is always a work around. I can only recommend the legal ones.
Thanks for your comment.
Looks like an absolute pain just to get the intake parts off....
The 4D56 is worse. Just a really grubby job, but important to do.
Your explanation of where the carbon comes from is wrong. It does not come only from blowby, most of it comes from EGR feeding diesel exhaust back into the intake, where the oil mist blowby mixes with it and forms the sludge. It's why we block off the EGR when possible, and fit a catch can to condense as much of the misty blowby to reduce the oil in the inlet tract.
The EGR system does not create the carbon, as I have explained before. It does however recirculate the gases that makes the situation worse. As I did in the video, installing a catch can is able to help with the problem. I have also stated that an EGR delete is not legal and therefore I do not recommend it.
@@MiracleMAX The EGR system DOES create the problem, because older diesel engines without an EGR system but with a PCV system do not clog up the inlet manifolds with carbon. The carbon is the black soot you see coming out of old diesels with no filters, so pumping that soot into the inlet and mixing with oil mist from blowby is exactly where the buildup comes from. It's also why diesels are far worse than petrols in this regard, because petrol EGR does not have the diesel soot.
@@einfelder8262 I'm not doubting that. But, the carbon is created by the combustion process. Previously, fuel used to pass the intake valves and help 'wash' them. With direct injection, only air is taken into the intake system - fuel is added in the cylinder. No 'washing' of the intake system takes place. Yes you are right, diesels are far worse than GDI.
I appreciate your view on the matter.
Thanks for your comment
@@MiracleMAXYou're missing the point. The combusted crankcase ventilation gases are directed from the crankcase to the air intake pipe, usually before the turbo. This oily mist travels with the fresh air to the inlet manifold. This is where it meets and mixes with the sooty, carbon filled EGR exhaust gas and forms the oily carbon sludge. There's two ways to avoid this. Either install an oil catch can and vent the remaining CCV gas into the atmosphere so only dry EGR gases enter the inlet manifold or the most preferred method is to block the EGR so only the oily mist enters the inlet manifold and burns up in the combustion chamber. I've actually managed to clean my valve stems of carbon (direct injection diesel) over a period of six months by blocking my EGR as the oily mist rushing through the inlet manifold venturis broke down the carbon on them. Obviously this isn't powerful enough to clean the chamber of the inlet manifold. I noticed the shiny valve stems when I removed the clogged inlet manifold. I soaked it in a diesel bath overnight. Pulled it out in the morning and all the sludge just fell out of it.
@@One_over_the_eight Glad it has worked so well for you.
Thanks for sharing your experience
Good oven cleaner spray cans x2 and pressure cleaner if not hot water
I guess you use what you have and the results will vary
Why not just delete the egr.? Your Air Fuel ratio will improve combustion, HP, and MPG.
As I have mentioned before, it is illegal
If you just blank off the egr all if this mess is gone and your oil keeps way cleaner for more kilometers. We all know this got nothing to do with regular oil change. the egr is the main component for this problem.
The carbon is created by the combustion process. The EGR recirculates some of those gasses to lower the NoX gasses due to temperature changes. To blank off the EGR is not legal, therefore I can not recommend it.
EGR is a really really bad idea. Logic suggests putting exhaust back into the intake will block with carbon.
Some other vehicles use variable valve timing to reduce NoX emissions and therefore do not have an EGR valve.
How about some one designs a donk that don’t make a donkey out of us !11
Too true!
Gasoline
What do you mean by gasoline?
EGR's are shit, sending exhaust air back into the intake, blanking plate and catch can.
Thanks for your opinion
All this anti pollution bullshit needs to be removed.
All it does is stuff engine's and ends up robbing power and using more fuel. 🤬🤬🤬
I guess manufacturers are required to fill emission requirements as stated by law to care for the environment. Emission levels have dropped due to these features - love them or hate them.