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Engine Specific Info and Questions => TDI Engine -General Info => Topic started by: svenakela on July 11, 2010, 06:00:20 am
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I'm thinking of keeping the EGR on my mTDI-swap, and how it could be controlled like the manual VNT setup.
On some engines the EGR recirculate as much as 30 % at idle but closes pretty quick. On other brands the EGR doesn't open that much and have a slower closing pattern.
How about letting the boost be the controlling factor instead of RPM and then having a spring loaded arm that regulates the valve?
My strategy is something like having the EGR recirculate about 15 % at idle and then close directly at boost.
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...on the other hand, it might be better for lower temp to let the EGR run a little bit open (http://en.wikipedia.org/wiki/Exhaust_gas_recirculation) even under load?
The first generation's of EGR's were vacuum driven, so it could be a first step to a simple but working reflow.
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I think you should have stuck with an e-tdi if you want the egr functional.
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I think you should have stuck with an e-tdi if you want the egr functional.
Answers like this makes me wanna keep the EGR even more.
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Seems to me the EGR form a Volvo D24T should be a direct swap, and free or cheap
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I think you should have stuck with an e-tdi if you want the egr functional.
Answers like this makes me wanna keep the EGR even more.
Why? ???
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There is zero benefit to an EGR on any diesel. Why in the world would you want something that INCREASES pollution just to reduce a small amount of smog producing chemicals by a small amount?
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I think you should have stuck with an e-tdi if you want the egr functional.
Answers like this makes me wanna keep the EGR even more.
Why? ???
Because EGR's existed long time before TDI's, and saying that an EGR only works with e-TDI is false. And that makes me wanna proof it works even more.
There is zero benefit to an EGR on any diesel. Why in the world would you want something that INCREASES pollution just to reduce a small amount of smog producing chemicals by a small amount?
I don't think any of the worlds vehicle producers agree on that one. Not the European MOT's either.
Never mind. It seems I have a different perspective on pollution than you guys.
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I'm not saying it couldn't work. I'm just saying you would have more control parameters and easier tuning if you used an ecu. Plus you would be able to control more pump parameters to decrease emissions. That's why people are criticizing you. You seem to be contradicting your goals with your means.
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Answers like this makes me wanna keep the EGR even more.
Why? ???
And that makes me wanna proof it works even more.
I understand now. But, you missed the point though.
Nobodys saying etdi is the only way to make it work, but to make it work well etdi is probably the best way. The manufacturers choose to control it electronically..
Rallydiesel is spot on, if its full on eco friendly you want, electronic control is the best way you will achieve this.
OM617 also has a point (cant believe i said it ;D), research EGRs and you will find that they reduce one type of pollution, but increase another, a lot. Thats before you even consider the extra wear on the engine, and the gradual choking of the intake which only serves to make your vehicle less efficient (worse MPG means more pollution per mile, except Euro MOTs dont test MPG so they dont reflect the true amount of pollution being produced). EGR doesnt help pollution, it helps pass a crude test, nothing more.
I don't think any of the worlds vehicle producers agree on that one. Not the European MOT's either.
The comments about worlds vehicle producers dont count. They make what the regulations demand of them. If the people writing the regulations miss the point and get it wrong (happens a lot in the world I live in), the world car producers still do what they say, otherwise they cant sell their cars.
Never mind. It seems I have a different perspective on pollution than you guys.
We arent pollution lovers, and we arent trying to put you down for what you're trying to achieve. We're saying you wont achieve reduced pollution with EGR, and if you really want to reduce NOX, in spite of what is said above & below, then etdi will be the best way to do it.
A quote from wiki:
EGR deletion
EGR deletion in diesel engines is considered justifiable by a wide range of people, including the environmentally conscious. Although deleting the EGR system results in increased NOx level; hydrocarbon emissions, particulates, carbon monoxide and carbon dioxide are drastically reduced. Furthermore, EGR deletion results in an increase in fuel economy as high as 25%. Exhaust gas recirculated back into the cylinders adds wear-inducing contaminants and increases engine oil acidity, which can result in an inefficient, poorly running engine. The increased level of soot also creates the need for diesel particulate filters to prevent environmental contamination.
http://en.wikipedia.org/wiki/Exhaust_gas_recirculation (http://en.wikipedia.org/wiki/Exhaust_gas_recirculation)
peace, MM :)
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We arent pollution lovers, and we arent trying to put you down for what you're trying to achieve. We're saying you wont achieve reduced pollution with EGR, and if you really want to reduce NOX, in spite of what is said above & below, then etdi will be the best way to do it.
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So, NOx is not pollution?
I've now been talking NOx and EGR for hours with one guy who's working with combustion at one of the big car companies, surprisingly(?) he has the opposite stand point. NOx is way more polluting than both COx and the soot (that's why they were used in mining vehicles before they were in use in road vehicles, to get better air in the tunnels). I'm swapping a pretty ugly IDI into a mTDI to get a betterand less pollutant engine - and the mTDI's from the mid-90's did meet the same requirements as the eTDI's - and the EGR is sitting there so why shouldn't I use it? If I want to be totally ECO friendly I wouldn't drive a car at all. Now I have the possibility to decrease the NOx by using the existing EGR I see no reason to not do it.
The eTDI controlling system for the EGR from a VW -95 has a temperature sensitive vacuum valve that opens when the coolant temp has reached a certain level. When the valve is open the adjustment is linear with fuel and air mass. Pretty simple.
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You have essentially answered your own question as to how to go about it then.
Your theory is to make it MORE eco friendly by adding in the EGR. What Rallydiesel is saying is, if you really want to, electronic control will surely improve things further still? Surely an electronic setup will give you further improvements in the area you want them? Nobodys talking about not driving at all, thats a ridiculous response.
Also, you're still ignoring the fact that your engine will suffer more wear with EGR (whats the carbon footprint on replacing your engine sooner) as well as reduced MPG (thereby increasing ALL pollution per mile, NOX particulate etc. MOTs dont measure pollution per mile, just whats there under zero load while stood still).
Some quotes you maybe missed:
"EGR deletion results in an increase in fuel economy as high as 25%"
"EGR also tends to reduce the amount of fuel burned in the power stroke. This is evident by the increase in particulate emissions that corresponds to an increase in EGR. Particulate matter (mainly carbon) that is not burned in the power stroke is wasted energy."
"deleting the EGR system results in increased NOx level; hydrocarbon emissions, particulates, carbon monoxide and carbon dioxide are drastically reduced."
"Stricter regulations on particulate matter(PM) call for further emission controls to be introduced to compensate for the PM emissions introduced by EGR. The most common is particulate filters in the exhaust system that result in reduced fuel efficiency. Since EGR increases the amount of PM that must be dealt with and reduces the exhaust gas temperatures and available oxygen these filters need to function properly to burn off soot, automakers have had to consider injecting fuel and air directly into the exhaust system to keep these filters from plugging up."
Sorry, we're only trying to help. Being so defensive about it is not going to attract others with good info to the thread. Nobody said NOX wasnt pollution either. You can do as you please, nobody is saying its not possible, were only trying to show the bigger picture regarding total pollution. Ie its not as simple as :"EGR reduces total pollution".
The guy who works with combustion, is he a pollution expert, or is he just another tech working to the guidelines given?
I wont come back to this thread, you seem to have your heart set on an EGR system regardless of the facts :-[
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After putting forth that may out of context half truths, I probably wouldn't come back either.
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Im back ;D
Sorry greasel, i wasnt quoting as fact, just pointing out info on the web, please feel free to counter with other info. I arent an authority on this, and am open to alternative theories. I judge your comment as 100% useless, so you can suck it my troll friend. :P
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<snip>
The guy who works with combustion, is he a pollution expert, or is he just another tech working to the guidelines given?
I wont come back to this thread, you seem to have your heart set on an EGR system regardless of the facts :-[
As I said earlier, we don't agree and will not either. I didn't ask to get more opinions about removing the EGR, I was trying to get a discussion started how to get it working.
In this case, I trust the guys at Opel's engine department more than loosely coupled facts taken from wikipedia.
Over n out, let this thread die.
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and saying that an EGR only works with e-TDI is false. And that makes me wanna proof it works even more.
So.....you want to prove you can make a valve that recirculates the engine's feces back to it's mouth, just to spite some people on the internet that know what they're talking about? Are you 15?
I don't think any of the worlds vehicle producers agree on that one. Not the European MOT's either.
Emissions regulations are a requirement, not an option. Manufacturers are forced to install an EGR because its the most effective way of meeting excessively stringent NOx emissions.
Now I have the possibility to decrease the NOx by using the existing EGR I see no reason to not do it.
I do, you don't know what you're doing.
I was trying to get a discussion started how to get it working.
And everyone has been showing you what an extremely poor choice that is.
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just let him hook up the EGR. he can clean out his intake in about 15k miles.. EGR valves get removed from everything i own. along with catalytic converters and restrictive air intakes..
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Only a problem with cooled EGR.
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Only a problem with cooled EGR.
Every single EGR, actually.
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So, NOx is not pollution?
I've now been talking NOx and EGR for hours with one guy who's working with combustion at one of the big car companies, surprisingly(?) he has the opposite stand point. NOx is way more polluting than both COx and the soot (that's why they were used in mining vehicles before they were in use in road vehicles, to get better air in the tunnels). I'm swapping a pretty ugly IDI into a mTDI to get a betterand less pollutant engine - and the mTDI's from the mid-90's did meet the same requirements as the eTDI's - and the EGR is sitting there so why shouldn't I use it? If I want to be totally ECO friendly I wouldn't drive a car at all. Now I have the possibility to decrease the NOx by using the existing EGR I see no reason to not do it.
The eTDI controlling system for the EGR from a VW -95 has a temperature sensitive vacuum valve that opens when the coolant temp has reached a certain level. When the valve is open the adjustment is linear with fuel and air mass. Pretty simple.
If you want to reduce NOx, then do water/meth injection to keep combustion temps down and you can also run a NOX reduction catalyst which will help clean up some of the Nitrous oxides produced.
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They used diesels in mining because the chemical reaction, if you remember high school chemistry, does not result the visciously poisonous (to animals including us) exhaust gas that a gasoline combustion equation does. It has nothing to do with exhaust gas recirculation or one being "cleaner" than the other.
it's LIKE the difference between bleach and solvent. They both clean stuff but very differently.
I also have to make my standpoint that the EGR is solely to pass a very useless and pointless emission control test. the fact that it chokes the intake over time reducing fuel economy is more than enough to say it doesn't work. and by work i mean reduce pollution on a bigger scale than over the course of today or tomorrow or this year i mean over the course of the engine's entire life.
IMHO if you are enviromentally concious at all you would not want an EGR system on your diesel engine. I have yet to find air quality regulations that actually work. Where I live every vehicle depending on year of manufacturing is required to pass an emissions test. On the older cars they run the exhaust through a contraption that calculates all these things. If your vehicle fails you have to "get it fixed" which usually means buying a new catalytic converter full of minerals that need to be mined in slightly less than enviromentally desired ways OR trash it and buy a new one... I really hope the negative enviromental effect of buying a new car and selling yours to a junk yard (or what ever you do with it) doesn't have to be explained.
This thread reminds me of the "how do i make a blow off valve work on my tdi?" threads.
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Wow, you guys (all of ya') seemed to really trigger on this subject!
First of all, I have no idea what kind of diesel you use with your vehicles. I have now one engine that recently passed 252 000 km (YM 2004), one at 190 000 km (YM 1996) and one at 200 000 km (YM 1983). The intakes are clean, a tiny tiny film of soot. That's all.
Me being 15? No, I'm actually only 13.
They used diesels in mining because the chemical reaction, if you remember high school chemistry, does not result the visciously poisonous (to animals including us) exhaust gas that a gasoline combustion equation does. It has nothing to do with exhaust gas recirculation or one being "cleaner" than the other.
it's LIKE the difference between bleach and solvent. They both clean stuff but very differently.
Yes, I follow you. But the use of the EGR-system was used in mines (at least here, what you did I don't know) to lower the NOx because it caused lung cancer and they did see that the water pumped out from the mines had bad pH-levels, and it was found out to be related to the NOx.
The amount NOx is far lower than the COx. NOx on the other hand is worse for water and land, and that's why there's a Zero-NOx goal for vehicle producers. The debate is now (again here, what happens in the states you know better than me) how and if Urea should be distributed at gas stations. There's more about it at http://www.volvotrucks.com/trucks/na/en-us/products/engines/epa10/scr/pages/scr.aspx (http://www.volvotrucks.com/trucks/na/en-us/products/engines/epa10/scr/pages/scr.aspx) (DEF is water and Urea).
I also have to make my standpoint that the EGR is solely to pass a very useless and pointless emission control test. the fact that it chokes the intake over time reducing fuel economy is more than enough to say it doesn't work. and by work i mean reduce pollution on a bigger scale than over the course of today or tomorrow or this year i mean over the course of the engine's entire life.
As I wrote above, I don't see the choking problem. With the facts I have about NOx compared to COx (I do know it's a give and take with their relation) I want to have a working EGR to lower the NOx. I live in a land with almost 100 000 lakes. I have seen what NOx does with lakes, and with some simple chemistry it was not difficult to see the NOx in the water. That's what I did in high school chemistry classes.
In this car I use quite a lot of biodiesel and in older cars FAME etc actually is reported to make more NOx than on dino fuel. To me it's another reason to use an EGR. There are more facts about in these pub's:
http://alexandria.tue.nl/repository/books/601471.pdf (http://alexandria.tue.nl/repository/books/601471.pdf)
http://www.ripublication.com/ijcher1/ijcherv1n1_4.pdf (http://www.ripublication.com/ijcher1/ijcherv1n1_4.pdf)
scottmandu mentioned water injection and that was also mentioned by one of the guys at the engine department I spoke to before. Could be another solution, worth checking up more, absolutely. I've been trying to book some hours at a workshop with car test bench and exhaust analysis instruments, but they are really busy so I'm not sure it will happen in months. Would be interesting if I could test it at the same time. Two of the racing teams I have as garage neighbours uses water injection on Porsche's and for power tuning it works for sure.
IMHO if you are enviromentally concious at all you would not want an EGR system on your diesel engine. I have yet to find air quality regulations that actually work. Where I live every vehicle depending on year of manufacturing is required to pass an emissions test. On the older cars they run the exhaust through a contraption that calculates all these things. If your vehicle fails you have to "get it fixed" which usually means buying a new catalytic converter full of minerals that need to be mined in slightly less than enviromentally desired ways OR trash it and buy a new one... I really hope the negative enviromental effect of buying a new car and selling yours to a junk yard (or what ever you do with it) doesn't have to be explained.
This thread reminds me of the "how do i make a blow off valve work on my tdi?" threads.
Well, we have the same thing. Failed test go fix it, that is. And as you say, getting a new car is better. And that's also the reason why I earlier in this thread wrote that if I want to be totally environmentally friendly I wouldn't drive at all. On the other I don't see the reason for that argument, I want to keep the emissions at a reasonable/as-good-as-possible level, why the criticism? EGR's are proved to work, but only if you not ask an american.