EGR valve ?

Status
Not open for further replies.

mk3forme

New Member
Apr 5, 2005
1,022
0
0
Lexington KY
Nick M said:
It can be a suspect, but it isn't guilty. A coolant mixture will only absorb heat from the engine, not transfer more.

And EGR lowers the chance of detonation, it doesn't increase. Keep in mind also, that when the computer gives the EGR command, the tables are different. That is why you need to have good enough gas.
So I am sensing you are thinking its better to keep it? Even with all the gunk that comes with it?
 

Dr Evil

No gun required
Aug 31, 2005
30
0
0
56
uk
Your better off getting rid of the egr as it does very little on the mk3 to prevent detonation, due to the fact that it only recirculates exhaust gas from the number 6 cylinder ......its a token gesture add on to keep the tree huggers happy .

With a properly designed and effective egr system Nox gases ( byproduct of combustion) are distrubuted from all the cylinders and help keep the combustion temps down thus preventing detonation .
 
Last edited:

mk3forme

New Member
Apr 5, 2005
1,022
0
0
Lexington KY
With that said its true it causes a hot spot on the number 6 cylinder. I wonder why that is where my gasket desintigrated at.
 

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
0
Redacted per Title 18 USC Section 798
Dr Evil said:
Your better off getting rid of the egr as it does very little on the mk3 to prevent detonation, due to the fact that it only recirculates exhaust gas back to the number 6 cylinder ......its a token gesture add on to keep the tree huggers happy.With a properly designed and effective egr system Nox gases ( byproduct of combustion) are distrubuted to all the cylinders and help keep the combustion temps down thus preventing detonation .

That's just plain wrong on several points. I'm tired of repeating about how EGR works in this car and the so called "benefits" of removing it so I'll just say the OP had better listen to Nick.
 

djordan97

New Member
Apr 14, 2006
199
0
0
Kennewick WA
jet jock can you post a link to one of those pages that have your results of the egr? and as for it only working on the number 6 cylinder some simple thought will invalidate that. yes it pulls exhaust from the #6 cylinder but it rerouts it into the INTAKE MANIFOLD that suplies air to all of the cylnders.
 

jimi87-t

Active Member
Oct 12, 2005
1,126
4
38
Colorado Springs
Food for thought, your EGTs will climb....a lot without the EGR in place. Right now I'm running without EGR, while cruising down the road at 60ish I'm seeing 1300 *F EGTs :aigo: This is off boost/ crusing. I don't see a big jump in temp at WOT (1350 -1400 *F). FYI, I'm running a stock CT-26 at stock boost, stock timing, stock injectors and stock ECU.

Before I go to my bigger turbo (or turn up boost at all) and install the MAFTpro setup I have lying around, I will be integrating EGR back into my setup. This will take a little work as I have a FFIM, but it will be worth the lower EGTs.

Also the stock intake mani does not dump the EGR into the #6 runner, if you look at a stock mani the EGR does bolt on to the mani by the #6, but in the casting of the manifold there is a "tunnel" that leads the exhaust gases to come into the mani right below the throttle body and in turn evenly distributing it all the cylinders.
 
Last edited:

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
0
Redacted per Title 18 USC Section 798
Some facts:

First, EGT is not a "token" effort. It's an effective way to reduce NOx emissions. If you think it's token try measuring NOx while it's disabled

Second, EGR does suppress detonation. This is true in any engine. That said I'm aware EGR isn't ECU controlled on the MKIII in the same manner as in newer cars but the ECU still applies a correction for what is assumed EGR flow. And although it's true EGR is disabled at idle and above 4200 rpm consider what happens when going up a hill without down shifting or at any other time the engine is loaded below 4200 rpm or WOT. Finally, some food for thought from Toyota's TCCS Factory Training Manual: "If EGR flow doesn't occur when commanded severe detonation will result".

Third, recirculated exhaust gas still reaches all cylinders even though it's introduced at the rear of the manifold.

Fourth, oxides of nitrogen aren't used to cool combustion gases. The entire point of EGR is to prevent NOx formation so if the EGR system is working there'll be very little NOx in the first place. Carbon dioxide (CO2) is what's used because it's the major constituent of the exhaust stream, cooler than combustion, and because it's inert to the combustion process.

Lastly, while I hardly consider myself a tree hugger some emissions facts: Each of the bad guys exiting the tailpipe effect the environment in different ways. NOx is the one responsible for the blown slop seen in the air. It's what puts smog in the word smog. It's also responsible for acidic rainfall. I've said it before but it's a shame the younger among us can't be transported back 30 years to places like Los Angeles or Denver to witness first hand the effects of NOx and the progress made since then. And since they're the ones who'll have to live in the environment the longest I continue to find it amusing they're so quick to advocate shitting on it.

jimi: No need to "curse" when not boosting. We're all forced to drive normal at times ;)
 

Dr Evil

No gun required
Aug 31, 2005
30
0
0
56
uk
Dr Evil said:
Your better off getting rid of the egr as it does very little on the mk3 to prevent detonation, due to the fact that it only recirculates exhaust gas back to the number 6 cylinder

Apologies i meant to say recirculates exhaust gases From No 6 exhaust port.

However the rest of my beleifs with this particular system stand ....and that is that the small amount of beneficial/combustion cooling gases accrued from one cylinder is not worth the excessive hot spot on the back of the head.
 

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
0
Redacted per Title 18 USC Section 798
Not only does a lack of EGR promote detonation and increase emissions but as jimi correctly pointed out also increases EGT. So the engine will run cooler that way? There won't be more thermal load placed on everything from the head to the exhaust and cooling systems? Ok, if you say so. Makes sense to me.

jimi: Just bustin' your balls a bit. I know you're a stickler for detail ;)
 

bigaaron

Supramania Contributor
Apr 12, 2005
4,692
1
0
50
Pomona, CA
www.driftmotion.com
I don't have one and I don't have any detonation issues :dunno:
If it is for detonation reduction why is there no egr on the Japanese engines?
The intake manifold and the intake runners stay cleaner without it too.
 

Dr Evil

No gun required
Aug 31, 2005
30
0
0
56
uk
Jetlock: Further apologies for quoting the wrong gas and direction of gas travel which yourself and Jimi are right about ,I had a moment where the knowledge didnt reach the keyboard and thanks for correcting me on it .....in fact its been a shitty day all round but thats another story .

I looked into egr very thoroughly during my rebuild before i decided to remove it and could find no real before and after evidence and benefits of keeping the system .

I have read Jimi,s posts before regarding egt but could not find any further evidence in support of keeping the system.

Is there any recorded data or undisputable evidence available in support of keeping the egr system on the mk3 supra ?

As far as emission and saving the planet go , what use is a system that draws off the environmentally harmfull gases off one cylinder and lets the crap from the remaining 5 cylinders belch out into the atmosphere?

Besides , would anyone driving a 3 litre turbocharged car be justified in taking any stand on the green house gas issue ?

If this was a fully integrated ecu managed egr system i,d be all for it .
 
Last edited:

jimi87-t

Active Member
Oct 12, 2005
1,126
4
38
Colorado Springs
I would assume the Japanese ECUs are mapped differently than the US ones. And the US ones have it there to meet the EPA standards here in the US.
If you run a stand alone, you are now in full control of what is going on and don't "need" it. But that is not to say that an EGR system would not be beneficial. But on the stock US spec ECU it thinks the EGR is there and is mapped for it.
 

Dr Evil

No gun required
Aug 31, 2005
30
0
0
56
uk
jimi87-t said:
But on the stock US spec ECU it thinks the EGR is there and is mapped for it.

So are you saying that All stock US ecu,s are mapped for egr and not just the california models ( as stated earlier in this thread ) ?

Does anyone know for sure of any differences between
Uk spec
Us spec
JDM spec ecu,s
 

jimi87-t

Active Member
Oct 12, 2005
1,126
4
38
Colorado Springs
Dr Evil said:
So are you saying that All stock US ecu,s are mapped for egr and not just the california models ( as stated earlier in this thread ) ?

It may not throw a code to alert inspectors of a malfunction (as pointed out earlier), but the ECU is still programed for it being there, as JJ pointed out:

jetjock said:
I'm aware EGR isn't ECU controlled on the MKIII in the same manner as in newer cars but the ECU still applies a correction for what is assumed EGR flow.
 

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
0
Redacted per Title 18 USC Section 798
Dr Evil said:
Is there any recorded data or undisputable evidence available in support of keeping the egr system on the mk3 supra
I thought I just gave you some. The factory manual. Plus every competent mechanic knows it. Plus anyone knows (or should know) EGT rises without EGR. As for JDM ecus, as pointed out the code is different. In fact the code is different depending on many countries. I've pointed this out numerous times in the past. Btw, I don't understand how anyone would "know" they aren't having detonation issues unless they were monitoring knock. That said the knock control system remains active if EGR is removed and when higher octane is used with a good tune removal shouldn't be an issue.

As far as emission and saving the planet go , what use is a system that draws off the environmentally harmful gases off one cylinder and lets the crap from the remaining 5 cylinders belch out into the atmosphere?
You must be joking. For someone who has researched EGR thoroughly you seem to have a poor understanding of how it operates and what it does.

Besides, would anyone driving a 3 litre turbocharged car be justified in taking any stand on the green house gas issue?
You appear to be confused about emissions. What does turbocharging have to do with the greenhouse gas issue? In fact what does NOx, CO, or HC have to do with it? The predominant greenhouse gas emitted by all gasoline powered vehicles is CO2 and as noted earlier CO2 is the number one byproduct of combustion. The cleaner an engine is the more CO2 it expels. Using your logic we're all guilty of massive pollution no matter what we drive and the cleaner a vehicle is under the current standard the more guilty we'd be. Does that make sense?

People are certainly free to do as they wish though. Even if it's a violation of federal law, craps up the air we all breathe, and could cause damage to their engines. I've got bigger fish to fry.
 

Nick M

Black Rifles Matter
Sep 9, 2005
8,897
40
48
U.S.
www.ebay.com
Unbelievable.

http://www.autoshop101.com/forms/h25.pdf Start with page 19 of 24. Then really pay attention on page 24.

http://www.autoshop101.com/forms/h61.pdf Read the whole article.

Funny how EGR will only work on cylinder 6, but a front facing intake manifold will deliver equially. And what part of water and coolant is a heat sink, not the other way around, do people not understand.

Big A, I believe you have your rides tuned safely, and are using good fuel, as already noted.
 
Last edited:
Status
Not open for further replies.