# what is the purpose of the EGR



## lovemysan (Jan 31, 2003)

I would like to know the purpose of the EGR system. And not how to search


thankyou


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## Rittmeister (Jun 29, 2002)

It injects hot exhaust into the intake stream, raising intake temps, to cut down on NOx emissions. Removing it might gain you half a horsepower, but it's also been known to cause idle and driveability problems when the valves and piping get clogged and/or stuck.

Hope this helps.


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## lovemysan (Jan 31, 2003)

Thanks for the reply. I simply don't have time to search for answers this week. I was seriously considering doing away with it. I have the whole engine out of the car so I'm cleaning the intake. I'm trying to prevent further crud buildup in the intake. As everyone knows its a pain to get it off.


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## nitestridar (Jun 29, 2002)

do away with it .. I will be getting mine out this weekend


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## HATEnFATE (Dec 24, 2002)

The SR20DE was designed to run without the EGR anyways..the only reason it's on your car is because the US requires it...


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## Centurion (Sep 5, 2002)

Actually, it _reduces_ combustion temps. And for this reason, your car may knock without it. I don't know what you have, but my GA knocked without it, so don't throw it away yet in case you have knocking.


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## seryusly (Oct 24, 2002)

what engine do you have? if you have the sr, you could just buy a jdm (i hate saying jdm) intake manifold. it doenst have any of the emissions stuff on there. your engine bay wont look as cluttered if you do it either.


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## Rittmeister (Jun 29, 2002)

Many of us SR20 guys have removed it. My car has a JDM SR20 in it, which of course has no EGR in the first place. I haven't had my car smogged here in Cincy yet (not due until Jan) but several other guys with the same motor have, and passed just fine. Unless you're in California, your catalytic convertor means a lot more than EGR.


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## Skinny G (May 9, 2002)

You really need to fully investigate these changes. EGR is designed to work at cruise. When you are at full throttle, EGR does not operate, so you are not losing any power at all. All you do by removing EGR is pollute more. And some of us have to breathe that crap.

G


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## Harris (Nov 11, 2002)

Removing the cat matters more when talking about having a clean environment, not the EGR.


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## Skinny G (May 9, 2002)

As I said before, some of us have to breathe this crap.


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## [V]igilant[D]river (Mar 6, 2003)

Theres no point in removing it unless you have a turbo,
although it does make your intake manifold dirty,
it's best to save the gas that isn't burned.
A.I.V. is for injecting air into the exaust manifold for clean burning NOx gases, EGR returns unused gas back to the engine.


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## Harris (Nov 11, 2002)

Skinny G said:


> *As I said before, some of us have to breathe this crap. *


And.... what are you trying to say? Removing the EGR will not increase emmissions or pollute the air by a significant margin as you are implying. Actually, I will get 2 tests done by the smog folks here and I guarantee you that the difference in NOx emmissions will be ever so slight.


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## bahearn (Jul 15, 2002)

EGR injects a stream of exhaust gas into the intake tract at part-throttle. This dilutes the intake charge, reducing combustion temperature. This temperature reduction causes a complimentary reduction in NOx generation. The EGR does not operate at idle or full throttle.

Removing a properly-functioning EGR will not gain any power, it will only clean-up the engine bay appearance and front-weight slightly.


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## lovemysan (Jan 31, 2003)

Well the egr is gone baby! The cat will stay. I attempted to clean my the USDM intake after 120k. Of course it was filthy. Lots of buildup the stuff after the egr ports was quiet difficult to remove. I basically decided to forget it. The new engine came in. It looked to have about 10k on it. Intake was nice a clean on the inside and that sealed the deal.

As for the Emissions I would think that people in boats, large trucks, motorcycles,airplanes,tractors etc would contribute much more emissions with there uncatalized exhaust. Than me without the intake with EGR funk buildup system in place.

Harris how about a third player for the comparision. A dirty usdm manifold.




BTW its a 91 SER. I'll change my sig.


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## bahearn (Jul 15, 2002)

Watch your mouth, dude.

Those sources you cite as gross polluters make up less than 5% of all vehicles operated. No way can they approach total pollutants spewed by the general driving public. Yes, NEW cars a very clean, but no matter how clean you burn gasoline, you get CO2 and NOx. You gross polluter, you.


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## Harris (Nov 11, 2002)

God knows how bad my intake manifold is. MY EGR is giving me issues with cold-startup, so I'll have to take it out soon. I'm gonna be doing an engine swap next summer too, so I don't really know if I want to take out the EGR, as the JDM engine will have no such headaches. I'm also in a personal dilemma, because I'm choosing between three choices, DE, DET and VE. My decision should culminate during the winter. I'll keep you posted on that.

And yes, cars pollute more on a gross basis, because there are more of cars than other pollutant machines.


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## HATEnFATE (Dec 24, 2002)

I would tend to agree with harris. I blocked my EGR before removing it and found that my engine idled better and ran cleaner and less rich. also, the manifolds aren't hard to clean...if you took your intake manifold to a shop I bet they would set it in a parts washer for a pretty cheap price...the other option is to put it in your dishwasher at home--just don't let anyone you live with see you doing it. The crap on the inside comes off pretty easy. I took both of mine to work and used a parts pressure washer......does make a diff......

Harris----if you have any old parts from your old engine you don't want--let me know--I would be interested in a few things if your willin to let them go......


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## bahearn (Jul 15, 2002)

Well, Jay, it sounds as if your EGR/BPT system needed work. Removing it SHOULD mnake no difference at idle or full throttle.


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## Harris (Nov 11, 2002)

HATEnFATE said:


> *Harris----if you have any old parts from your old engine you don't want--let me know--I would be interested in a few things if your willin to let them go...... *


Sure, just keep track of any posts I make in the Mechanical/OEM part-out section of the sr20forum site. I am still planning on what I will be doing, as I have a lot of ideas, but no concrete commitment to what I want to do. I guess time will tell. However, I will make my decision and purchase the engine of choice no earlier than June/July of '04, so we still have plenty of time.


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## HATEnFATE (Dec 24, 2002)

It probably did need work--when it was on the car at idle I would have a miss pretty often but as soon as I disconnected the EGR it went away....it might have been stuck in a constant "on" and been adding horrible gasses into my chambers during idle....


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## lovemysan (Jan 31, 2003)

So what we need to know here is how much more the sr20 pollutes without the EGR. Like I said I still have my cat and in good working condition. I Don't have a parts washer to clean all those passages and ports with. It was annoying just to get it all apart.


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## bahearn (Jul 15, 2002)

Some people pass their emissions inspection without EGR. I have no idea as to quantitative difference in NOx without EGR.


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## StevenLK (Jul 15, 2002)

dumb kwesjun but its got me confused. is the EGR that piping that is rite where the VC, where u have the cap to pour motor oil into? is it just to the rite of that?... if not what is that for? i knocted it was oily, so i took it off kause it was crackd and put a silicon tube that is closed and no air gets threw unless i rev the engine, but when ther is no tube i have to hold the opening that is on the intake mani. klosed kause the engine will cut off.. .


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## ace (Aug 8, 2002)

can anyone show me where the EGR is located and how it looks like ?

hoefully cleaning it would eliminate my cold hard start problems.


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## Centurion (Sep 5, 2002)

It's the "disk" in the middle. Are you sure you want to f. with it?
Nasty frozen bolts and all...


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## toolapcfan (Jul 10, 2002)

If we really wanted to save the ozone, we'd quit eating beef. The worst ozone depleting agent is methane and enough of it is produced by cattle that they are the leading cuase of ozone depletion. If we were smart we'd do like they're doing over landfills now, and capturing that methane so that we can use it to generate electricity, not to mention then it won't deplete the ozone.


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## Gsolo (Sep 11, 2003)

I just wanted to add in here that there is no reason to remove the egr. it doesn't affect your performance either way. in actuallity having a proper working egr is better than none at all cause it keeps the combustion chamber cooler, and if you know what you are doing on some vehicles you can advance timing a little more than if you didn't have egr. besides, egr has been around since like the 50's, if it hindered performance in anyway we'd know by now. and whoever it was that mentioned trucks and motorcycles...diesels today burn cleaner than cars and newer motorcycles are starting to have more emissions like cats and charcoal canisters.


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## Harris (Nov 11, 2002)

Oh yes EGR does hinder something, which is why people remove them. Its called smooth idling. 

Oh, and to prove that EGR does not do anything to significantly reduce pollution, here is an example. A buddy of mine had a PRISTINE condition B13 SE-R that he just sold to someone. The car was stock engine wise (just had an intake and red VC), the only non-stock thing being that he had an aftermarket cat-back exhaust. The guy who bought the car from him went to the emmissions and failed! It was determined later on that the cat was not working right. 

Another story, a forum member removed his EGR because of idle issues. The car was otherwise perfect, with a working cat. And he went to emmissions, he passed with flying colors. 

So what's the moral of the story? EGR is just a crappy system that has only marginal gains to be achieved in comparison to the costs associated for having it.


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## Gsolo (Sep 11, 2003)

i'm not arguing that you shouldn't take egr off. but there is a reason for it being there. and it should never effect idle if it does its not working properly...but if its not working properly just scrap it cause cost of replacing usually isn't worth it.


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## Harris (Nov 11, 2002)

The reason for it being there is to get us mad once our idle starts getting weird.


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## Gsolo (Sep 11, 2003)

btw, when i said that egr has been around since the 50's..well i lied. i was thinking pcv at the time cause i've been trying to figure out a pcv problem on my chevy, i fear blowby but anyhow, still egr has been around since like 70's for sure.


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## calichaz (Oct 22, 2003)

ok, whats the proper way to block off the EGR and BPT?? I just dropped like 300$ on a new EGR and BPT to get it to pass emissions only to find out my cat was gone, and my car ran worse after the new stuff was put on!! beacuse as it sits, my car BARELY runs, Im thinking it might be a clogged pre-cat in the manifold? (my header broke) Im doing a swap soon, but would like to get my beast running cause shes easy on the gas,,my Jeep is not.


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## pearl200sxse (Jun 14, 2003)

Rittmeister said:


> It injects hot exhaust into the intake stream, raising intake temps, to cut down on NOx emissions. Removing it might gain you half a horsepower, but it's also been known to cause idle and driveability problems when the valves and piping get clogged and/or stuck.
> 
> Hope this helps.


would you reccomend doing it?


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## Harris (Nov 11, 2002)

If it is giving you any problems, or if you would like to see less clutter in your engine bay, then go ahead and remove it. Being that you're in FL, you don't even here to worry about yearly smog-checks. Remove it!


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## pearl200sxse (Jun 14, 2003)

Harris said:


> If it is giving you any problems, or if you would like to see less clutter in your engine bay, then go ahead and remove it. Being that you're in FL, you don't even here to worry about yearly smog-checks. Remove it!


i have a ga16, and mine popped off one time and it sounded like my car was bogging out. why was that?


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## Harris (Nov 11, 2002)

I think that you are confusing the vacuum hoses that come off of the intake pipe as being part of the EGR system. I had one of my EGR hoses come off once, and I remember feeling no difference with or without that hose being on.


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## pearl200sxse (Jun 14, 2003)

Harris said:


> I think that you are confusing the vacuum hoses that come off of the intake pipe as being part of the EGR system. I had one of my EGR hoses come off once, and I remember feeling no difference with or without that hose being on.


Theres a copper tube that leaves my header, goes into my intake manifold... the bracket broke, and it sounded like the car was bogging out. when i put it back in place it sounded fine. is that due to the engine taking in constant non filtered air?


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## James (Apr 29, 2002)

yes it is depending on what side of the bracket you are talking about... if you're talking about the pipe on the back of the intake manifold that runs into the egr then yes.


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## pearl200sxse (Jun 14, 2003)

James said:


> yes it is depending on what side of the bracket you are talking about... if you're talking about the pipe on the back of the intake manifold that runs into the egr then yes.


I have a 96 se ga16de and it is a copper tube on the right of the exaust manifold, it runs to the intake manifold behind the throttle body. can i tap this off? if i do so what benefits do i get? my car has 110,000 miles: so im pretty sure its clogged beyond belief. like i said i noticed when it came out mu car sounded like crap. i think it is because the gasses came out through the hole, but i wanted a second oponion.


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