cefiro8701

iTrader: (7)

who makes em?

will this particular item work?

http://cgi.ebay.com/ebaymotors/ws/eB...m=280493044481


i have a janky-rigged set up right now and it's throwing a code. I'd like to just block this sumb1tch off.

njmaxseltd

iTrader: (19)

Whats the purpose of blocking the EGR? It's purpose is to increase gas mileage and reduce emissions when your crusing. It's not operating when your idling or accellerating.

Seems like a worthless mod.

cefiro8701

iTrader: (7)

i have an 00vi installed.

if there's some way to keep it.I'd have done it.

but there wasnt.

i don't mean to sound like a douche but I wasn't asking you if it's worth it. I was asking for an opinion about the fitment of the block off plate.

aackshun

iTrader: (3)

What's wrong with JB welding a penny?

ChrisMan287

iTrader: (34)

This.

But for $7.50 shipped just give that one off eBay a shot.

cefiro8701

iTrader: (7)

i think my jb weld fix ruined my threads in that area.

I'd like my EGR back for said MPG "gains."

So...

I'll run a copper tube from the EGR to my Intake Manifold.

schmellyfart

iTrader: (46)

Using the 00 guide tube was out of the question?

I certainly haven't lost any MPG since blocking off my EGR when I installed my 00vi in March 2010. Take a look at all of my fill ups since I bought the car in '08 if you want.http://www.fuelly.com/driver/schmell...ima/log/page/1

cefiro8701

iTrader: (7)

didn't come with one.

just a block off plate.

adroitcaptor

schmellyfar - It seems that you are not taking in consideration that the VI is helping your MPG over stock. Thus you still could be losing potential VE without the EGR. Driving style will dictate the coefficient. It is worthwhile work to install the EGR with the 00VI.

If you are not using an EGR you are doing senseless damage to our environment. Not really all that 'cool' IMO. I am not hippie; I do think [gross] neglect is unintelligible and in no way admirable. Why do people think all these systems were installed? Are the engineers at Nissan really that much dumber than the common population?

OP - It is too easy to go to your local metal shop and have a proper block-off plate fab'd. This is not likely to cost any more than your eBay suggestion and guaranteed to work. If you have a metals shop you can do the same.

Do work the correct way and avoid issues in the future (like the one stated above).

VQ'rInWLA

iTrader: (83)

Pare, if youre thinking about reinstalling your EGR, LMK. Ive been contemplating doing mine also....We could set up another day like yesterday with Charles too. Itd be an all EGR day

Leo_Koneval

iTrader: (4)

If I remember correctly, the EGR doesn't help with MPG, or at least not as much as you would expect, it is more for emissions than anything else.

The EGR pumps inert exhaust gas back into the combustion chamber to cool it down and reduce NOx and reduce your chances of getting engine ping/knocking.

I think without burning those exhaust gasses our cars would actually be more efficient, but at a cost of higher combustion temperatures.

Bassbreaker

iTrader: (8)

I thought it was to burn off gas that never got burnt during initial combustion? So you are using the most gas you can which you put into your car vs letting some of it just go out into the atmosphere. I imagine the % of gas that is still in the exhaust wouldn't be much over 5-10% gas fumes...so it wouldn't make a dramatic change to your mpg's...just my 2 cents

schmellyfart

iTrader: (46)

Remove it and buy a 00 guide tube. Supposed to be a direct fit.

asand1

iTrader: (1)

EGR is meant to Recirculate inert exhaust gasses into the engine to reduce temeratures in an attemt to reduce NOX or "oxides of nitrogen".http://www.epa.gov/oaqps001/nitrogenoxides/

Blocking off the EGR MAY cause detonation or "pinging due to higher combustion chamber temps.

"Are the engineers at Nissan really that much dumber than the common population?"
The engineers at Nissan didnt install EGR because they like it, they installed it because without it, the EPA won't allow vehicles to be sold in Amerika. Nissan engineers would rather put air and fuel into the combustion chamber (higher volumetric effeciency) and gain power and economy.

t6378tp

iTrader: (69)

it looks like it would work fine, if you buy it report back cause I already saved this in my watch file

adroitcaptor

The Prefix of Information

Some possibly confusing information exists in this thread. I would like to clarify this EGR issue for the sake of those who might read [after search] this thread. I will give some general operational information and then address previous comments.

Disclaimer: The following is written in abbreviated/non-scientific form. I composed this from my own understanding and I do not claim to be infallible. Go gripe at someone else (but feel free to correct any errors you find) if you do not like it. Would you like to know more? [movie reference]

A little history: We used to run gas with a tetra-ethyl lead additive. The sales of this leaded fuel stopped because of it’s polluting byproducts. When this happened engine design needed to change. Originally this additive kept combustion temps cool; effectively raising the octane. (Octane is actually a misnomer of sorts... see the science section; I digress. This cooling effect has two reactions (*contingency not explained here): reducing combustion temps and thus Nox emissions. Though the two are connected they still remain positive effects one to us performance geeks and the other to us environmentalists. This all changed in the early 70's when lead was deemed unsafe.

Some science:
NOx is a short-hand term for mono-nitrogen oxide(s). The two most prevalent elements, in our case, being Nitric Oxide and Nitrogen Dioxide. (Let us avoid isomers for now; I believe there is 9... which isn't). These oxides are produced at around 1300C (2372F) during the combustion process. The production drastically increases at aprox. 2800F. (FYI - The amount produced from 2800F to 3200F is exponentially more than from 2400F to 2800F.) Eventually down the line in the earth’s natural cycles we get smog [a photochemical haze] and eventually, when it rains, ‘acid rain.’

'Octane', as stated previously, is somewhat of a misnomer. It should read, at the very least, octane rating. Really what 'octane' stands for, as most of us know it, is a number [on a linear scale] to express a fuel's resistance to knock. (Do not get me started on the misconceptions about knock or you will get another one of these posts...) At any rate, back to science. So how do we find the 'octane' of a fuel? Well we use our two set points given [selected] by some dude (forget is name) back in the early 1900s that worked for the Ethyl Corporation. He said, iso-octane (2,2,4-trimethylpentane) is 100 and n-heptane is 0. If your fuel has the same knock resistance as 90% iso-octane and 10% n-heptane (by volume) your gas is 90 'octane.'

Octane, the real octane, is a hydrocarbon chain. Ergo [movie reference] it is a stable alkane, of which there are 18 isomers. I only bring this up because of of those 18 is... yes you guessed it, iso-octane. A hydrocarbon chain is simply as it sounds - a chemical compound configuration composed [yes it was on purpose] soley of single bonds between carbon and hydrogen molecules (with no branches). This is only interesting because you have probably heard of many of the alkane family and the synonyms for alkane such as paraffin and saturated hydrocarbon. The simplest of which is methane, ethane, propane, toward the more complex 'butane', relatively listed.

adroitcaptor

The ACTUAL System... FINALLY!

Disclaimer: The following is written in abbreviated/non-scientific form. I composed this from my own understanding and I do not claim to be infallible. Go gripe at someone else (but feel free to correct any errors you find) if you do not like it. Would you like to know more? [movie reference]

Understanding the EGR system: EGR systems vary greatly depending on year and make. Some work solely off of vacuum while others have mechanical and/or digital parameters. But as a very basic operational overview, the EGR takes gas (not the fuel kind) from the exhaust manifold, and re-introduces it to the intake manifold.


Why recirculate the exhaust?:

Leaded - If we compare 'leaded fuel' to 'unleaded fuel' [oh how we learn] we find that we 'can' have the same fuel on a base level. The only difference is whether or not it has an additive. Why is this significant? Well that 'lead' that they put in the fuel helped lower combustion temperatures. This in return raised the octane level. The bad part is the nasty crap we put into the air. (If you read my previous post you already knew that.)

Unleaded – Now we have a lower octane and higher engine temps. How can we lower it AND make the hippies happy? An EGR my friends, an EGR. (BTW – if you did not know knock is very bad for your engine.)


How does it really work: (This is the part where I keep it really simple and easy to understand.)

So the theory is to utilize the exhaust gas that has, as a majority, already undergone an oxidation process. In doing this we accomplish 2 things. Increase volumetric efficiency (VE) and lower combustion temps.

Volumetric Efficiency is a fancy pants term to describe how efficiently an engine burns fuel. Many factors come in to play here... too many to list. But 1 applies to the subject at hand so let's look at that. During lower RPM and closeTB RPM the vacuum is much higher than otherwise. This vacuum directly correlates to how hard the engine has to work to get air, and thus fuel, into the combustion chamber. There are many ways to overcome this but some common are Ram Air Induction, Forced Induction, and YES! you guessed correctly again, an EGR system. Even when the intake manifold is at 'high' vacuum the exhaust manifold is still under pressure. If we take that higher pressure gas and introduce it, in 'smaller' amounts, to the intake manifold, we reduce that present vacuum... to a degree. This is where most people get off track. This process does not, I repeat, does not displace your AF mixture. We can delineate from the presence of vacuum, that the engine is not pulling as much gas (not the fuel; but with fuel) as possible into the combustion chamber. If it was, it would not be under vacuum. You can have a perfect stoichiometric [sic] charge but still not have enough of it. Now I will admit, this is not God's gift to the auto world by means of achieving near perfect VE, but it helps.

And the other mentioned benefit - cooling the combustion charge. This is good for the hippies and those of us who like to breath. By lower that temp below the 'critical' 1300C we do not produce near as much NOx emissions. However, this also helps our VE. This on a smaller scale than the above, but a lower combustion temp means a more controlled temp. By realizing this effect we reduce knock. If you do not think that helps VE then you do not understand engines. At any rate now both parties are happy [or should be?].

So there you have it. That is how the EGR system works. I hope I have kept the later post simple enough to be readily understood.

I really do not care to argue WHY we had to use the EGR system over your epic invention OR the absolute effectiveness, thereof, expressed scientifically, of how much this helps reduce emissions. The fact it does help, and we do not have a choice, is enough for me. Mostly because it is like arguing Bush's motivations in the political arena... who REALLY knows; only 1 person. [lights fire]

adroitcaptor

/agreed sir. I was not attempting to say that the Nissan engineers came up with or volunteered for putting the system in. What I meant is that your engine has been designed around it's existence. Since it does have an effect on your combustion parameters messing with it would require the vehicle to be tuned in order to compensate for its removal.

I will give you credit that you did not form the above as a statement. However, if you could burn, without penalty, 5-10% more fuel, that would make for a very dramatic increase in performance. Just a thought...

To all – Please, keep your EGR intact and in functioning order. Polluting the earth is one of the most pointless and adverse pass times. Just like our economy, the pragmatic laziness of former generations is screwing OUR future. Turning and doing the same to future generations is idiotic. Do not just pass this issue up, do your part. [joke incoming] Al Gore would want it that way... as long as he can profit from it.

Please be lenient with me. I spent all the time I have writing these 3 posts. I do not have time to proof them. Break time is over; back to work for me. Sorry in advance!

ken85

iTrader: (1)

Wow... Well if you think removing the egr system off a few cars here and there will destroy the environment. Look at the impact building all these /hybrid/ cars causes. Those are the worst because people buy them b/c they are "Environmentally friendly" and are actually more harmful to produce than driving around your average vehcile for 20ish or so years.

I just felt like saying this b/c it is not really an environment killer to remove it. I am pretty sure eliminating the catalytic converter and proper exhaust components causes alot more damage than removing an egr system.

adroitcaptor

How many is a “few cars here and there?” Please put an exacting figure on your statement.
How many cars, that have their EGR system removed, does it take to start to “destroy” the environment?
Who regulates and or keeps track of how many cars remove their EGRS so we do not exceed the 'few'.

None of my posts compared one polluting system to another. They were about the EGRS
Your statement holds little validity unless you have some comparative figures. Many postulate much; few prove little.
I am not really sure what your point of posting this was. Why not mention the environmental impact of factory farms (CAFOs). IC factory practices in 'waste distribution.' Or how about the gross differences of regulation standards between the EPA and TCEQ; how the later was trying to pass off one of the biggest polluters in America (by hazardous percentile).

Define “environmental killer” please.
You are pretty sure? You are giving other people advice and correcting me after being “pretty sure?” To add you are pretty sure about a different system, not the EGR.
Your justifications are absurd and lack rationality. Simply because one thing, in a larger system, prevents a greater amount of pollution, does not give cause to remove another. [causality lawlz]
Clearly you missed the logic in, “I really do not care to argue WHY we had to use the EGR system over your epic invention OR the absolute effectiveness, thereof, expressed scientifically, of how much this helps reduce emissions. The fact it does help, and we do not have a choice, is enough for me. Mostly because it is like arguing Bush's motivations in the political arena... who REALLY knows; only 1 person. [lights fire]” and, “To all – Please, keep your EGR intact and in functioning order. Polluting the earth is one of the most pointless and adverse pass times. Just like our economy, the pragmatic laziness of former generations is screwing OUR future. Turning and doing the same to future generations is idiotic. Do not just pass this issue up, do your part. [joke incoming] Al Gore would want it that way... as long as he can profit from it”

In analyzing the impact of your statements I qualm as it presents more information in which I was attempting to calm. [internal homophone joke] The facts remain, as some have been stated above. There is no benefit to removing the EGR assembly and many to keep it. Furthermore by making these statements without any evidence whatsoever, even subjective support, you are taking a thread about EGR block-off and turning it in to an environmental debate. This was clearly not the intent of my post (as shown above).

BTW - I do not understand why you quoted me, as if you were going to refute or correct what I was saying, and never addressed it or purposed your reply toward its intent.

This is not a me vs you post. I am not responding to continue an assumed debate or argument. Once again, my only effort is to undertake the correction of misleading posts. I am constantly bothered by people giving poor or flat-out wrong information. A perfect example (in antithesis to yours) is Asand1's correction. Though I believe he missed the spirit of my post he brought an issue to light and addressed it intelligently. I do not believe he was 'wrong' by any standards to do so. In fact, if anything, he encouraged me to write a more extensive and encompassing post. His discourse provided, inherently, that my former comment was misleading/confusing/etc. (He also eluded a planetary [a mechanical metaphor] issue – there are better ways to design a system that accomplishes the same more efficiently.)

If it helps you digest what you see as rhetoric, I fab'd and installed a block-off plate for my '78 Z (4 years ago).

Trini Boom

iTrader: (5)

:metalmax:

ken85

iTrader: (1)

I didn't read your reply because I am not going to argue with somebody that likes to try to sound fancy

ampire

iTrader: (12)

Crusher103

iTrader: (10)

I deleted my EGR a long time ago, didnt notice and spikes or decreases in gas mileage and the car still makes it past inspection.

Rood

iTrader: (15)

Same with me. Except I haz no inspection.

Tmars

iTrader: (4)

I belive you are confusing the word "Intelligent" with your less intelligent word. FANCY.

hornepirate

iTrader: (23)

wow smh... You do realize in 01 Nissan decided to block off the EGR right? 01 maximas have a factory EGR block plate on them.

j-dawg

As long as we're discussing EGR, I'll throw in a few graphs from a homework assignment I had a few weeks ago, wherein I was to make a MATLAB program crudely simulating a dual-cycle diesel engine and study the effects of changing various operating parameters, including EGR. This was a purely thermodynamic analysis; the system was modeled as air with the ignition modeled as heat addition, so there are obviously simplifications, but the basic premise is correct. The model holds all other variables constant, so the variation you see here is due purely to EGR.

Below is a set of P-v diagrams describing the combustion cycle with varying amounts of EGR, from no EGR to half of the exhaust gas being recirculated.


As you can see, increasing EGR decreases the maximum pressure in the cylinder throughout the cycle.

Below is a plot of efficiency and work output versus EGR fraction.


This image is a bit misleading: before drawing too much from it, note that there is no correspondence between the left and right axes. The increase in efficiency is on the order of 1% when comparing no EGR to 50% EGR, but for that slight increase in efficiency you lose something like a third to half of your torque (work).

So really, while EGR may help your mileage a tiny bit, it's far more useful as a tool to reduce emissions. If you're concerned about performance, don't be: most cars' EGR systems aren't active when you're at WOT as well as at idle. There's absolutely no good reason not to have a functional EGR valve - it reduces harmful emissions and (marginally) improves mileage.

If anyone's interested, I can upload the code that produced the above results. You can tinker with physical parameters of the engine (this was for a 4L 4-cyl engine; stupid, I know, but it was the assignment) and perform studies on changes in EGR, air-fuel ratio, compression ratio, and the cutoff ratio (it's a dual-cycle diesel). It's pretty cool to play around with, and I was surprised at how enlightening it was to write. You'll need MATLAB to run it, though.

j-dawg

It actually just occurred to me that I can adjust the parameters of the program to simulate a 500cc cylinder running on an ideal gasoline cycle, ie one cylinder from an ideal VQ30 running at stoich. I'll do that and post the results when I get a few minutes free...until then, I have an exam in that same class tomorrow, which is why I'm on the .org at 3.30am.

ndscrub212

iTrader: (4)

Has anyone bought the one off ebay??? Can you let us know if it works. I have a 02 maxima and am putting a 06 engine in and I need to block off the egr. Let me know

JSutter

iTrader: (46)

The plate should work, but you can make one for less.

ndscrub212

iTrader: (4)

What would you suggest using if you were to make one? How thick would you make it?

TravisCadello

thought about blocking mine off but after reading all this ill keep it.