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grayscale
03-09-2009, 11:22 PM
Note-This guide is based on a 1992 5sfe engine, but most other engines are fairly similar.

First things first- why are you removing the EGR system? The are only two reasons one would remove the EGR system. One of them is that it is no longer working properly and you don't really have any use in replacing it, i.e., you don't want to spend the money on it. The other is, you don't want all the excess garbage that builds up in the system over time going into your nice shiney new rebuild. Oh, and maybe you're tossing out every little piece you can live without in an effort to shed some wight. Other than that, there is no good reason to remove it. It will not net you any hp gains. In some states it is required to pass emissions inspections, so if you're unsure, find out before you go through all the trouble. Lastly, you may actually see a small drop in your in your fuel economy. Why? Well, to best explain, here's a basic rundown on how the EGR system works-

Exhaust gas recirculation (EGR) systems were introduced in the early '70s to reduce exhaust emission. Oxides of nitrogen (NOx) are formed when temperatures in the combustion chamber get too hot. At 2500 degrees Fahrenheit or hotter, the nitrogen and oxygen in the combustion chamber can chemically combine to form nitrous oxides, which, when combined with hydrocarbons (HCs) and the presence of sunlight, produces an ugly haze in the sky known as smog.
The EGR valve recirculates exhaust into the intake stream. Exhaust gases have already combusted, so they do not burn again when they are recirculated. These gases displace some of the normal intake charge. This chemically slows and cools the combustion process by several hundred degrees, thus reducing NOx formation. The EGR system must precisely control the flow of recirculated exhaust. Too much flow will retard engine performance and cause a hesitation on acceleration. Too little flow will increase NOx and cause engine ping. A well-designed system will actually increase engine performance and fuel economy. Why? As the combustion chamber temperature is reduced, engine detonation potential is also reduced. This factor enabled the software engineers to write a more aggressive timing advance curve into the spark timing program. If the EGR valve is not flowing, onboard diagnostics system will set a code and the ECU will use a backup timing curve that has less advance to prevent engine ping. Less timing advance means less performance and fuel economy.

Now you can see how removing the system can reduce fuel economy, but also how an aging fouled system can do the same.

List of things you'll need to complete removal-
1. EGR module block off plate.
2. EGR hard line block off device.
3. Rubber vacuum caps.

I suggest going to the auto parts store and picking up a box of vacuum caps of various sizes, they don't cost much.


So on to the nuts and bolts of things. I have provided a drawing below thanks to Toyota so you can familiarize yourself with the parts we'll be talking about.

http://www.celicatech.com/gallery/files/5/3/3/2/bgbegr1.jpg

In the above schematic, you'll see several lines I have marked. All of them except for number six are vacuum lines. Depending on the condition of your engine, some of these lines may still have factory foam insulation on them which will need to be removed so you can trace the lines. Note: some vacuum lines have numbers on them(1-9)-these numbers are not the same as in the drawing above, ignore any numbers on lines.

Lines 1-2 are the two lines that run between the egr modulator and the throttle body(tb). These will need to be removed and the two ports on the tb capped with vacuum caps.
Lines 3-4 both run down to the egr vsv, which you can see is mounted on the back of the head. These lines need to be disconnected from the vsv, and also on the other ends from the egr modulator and egr valve. If you would like, you may also remove the vsv, it is not used for or attached to anything else.
Line 5 goes between the modulator and valve. Once you remove it you are free to remove the egr modulator.
Line 6- as you can see I have underlined line 6 in red, and in the upper portion of the drawing I have highlighted in bright pink. This is a hard line. It extends from the bottom of the egr valve to a port on the head just below the intake manifold on the transmission side of the head.(bottom pic is a little misleading) From this point you will need to unbolt the egr valve from the intake manifold. Now you will need to get a wrench, or whatever you can fit down there, and and undo the large nut on the end of the egr tube. Remove egr valve and tube from engine.

At this point I'd like to I wish I had more pictures of the process for you, but I did this several years ago, and got around to do the write after several requests. Though as soon as I do another for some one else I will add more pics.

So now that you have the tube removed, cut it in half! Do it however you like, we won't be using the tube again. What we do need is that big nut on the end. What about the big hole in it you say? You have two choices- try to find a cap nut this size with the correct threads(good luck) or make what you need. Now what I did was took something small enough to fit in the nut but bigger than the hole, in my case a large ball bearing, and welded in place. I realize not everyone can do this so I've had other ideas. One thing you could do is find a slug, looks like a washer without a hole, or a dime or penny, or something of similar size and either jbweld it in or use rtv type gasket maker to seal it in. Once you have this sorted out, use some thread sealer and put the nut back where you found it on the back of the head.

After that it's simply a matter of putting your blockoff plate and sealant or gasket over the hole where the egr valve was. :bigthumbu

Below are some pictures of the finished product.

Nut cap on back of head.
http://www.celicatech.com/gallery/files/5/3/3/2/100_21189.jpg


Blockoff plate on back of intake manifold.
http://www.celicatech.com/gallery/files/5/3/3/2/100_21187.jpg


Capped off throttle body with no egr junk in the background.
http://www.celicatech.com/gallery/files/5/3/3/2/100_21921.jpg

Here are some more photos submitted by Smaay-
Clear view of mounted EGR, you can see where it connects to.
http://www.celicatech.com/gallery/files/6/1/6/DSC03395.JPG
http://www.celicatech.com/gallery/files/6/1/6/DSC03393.JPG

Clear view with complete EGR assembly removed.
http://www.celicatech.com/gallery/files/6/1/6/DSC03391.JPG
http://www.celicatech.com/gallery/files/6/1/6/DSC03392.JPG
http://www.celicatech.com/gallery/files/6/1/6/DSC03390.JPG

RedRkt01
03-10-2009, 12:24 AM
I vote for sticky.

grayscale
03-10-2009, 12:33 AM
I vote for sticky.
Already done! :bigthumbu

RedRkt01
03-10-2009, 12:36 AM
Ha! By you?

grayscale
03-10-2009, 01:19 AM
Winner winner chicken dinner!

Ads28
03-10-2009, 01:58 AM
nice write up..will add this to the To-Do list for the celi

CriScO
03-10-2009, 05:02 AM
Nicely done Cannon.

But what would I do with my 25 feet of red vaccum hose?!? :hehe:

Shadowlife25
03-10-2009, 05:30 AM
Great write-up Cannon. :D

I do feel that I should add one caveat:

This is by no means legal in the state of California on an emissions controlled vehicle which will see use on public roadways.

grayscale
03-10-2009, 07:21 AM
Nicely done Cannon.

But what would I do with my 25 feet of red vaccum hose?!? :hehe:
http://www.celicatech.com/gallery/files/5/3/3/2/hookah.jpg

grayscale
03-10-2009, 07:24 AM
I do feel that I should add one caveat:

This is by no means legal in the state of California on an emissions controlled vehicle which will see use on public roadways.
Gotcha covered :bigthumbu

In some states it is required to pass emissions inspections, so if you're unsure, find out before you go through all the trouble.

taibones
03-10-2009, 03:26 PM
the nut that goes in the back of the head is a m18 x 1.5 plug i found one at car quest for less then 3 bucks

MrWOT
03-10-2009, 05:02 PM
I wouldn't disable the EGR unless you have over 91 octane available anyway. Helps more than it hurts.

Cooled EGR is better. I've been pondering an alcohol injector in the EGR, vaporizing the alcohol would absorb a lot of heat.

grayscale
03-10-2009, 09:11 PM
the nut that goes in the back of the head is a m18 x 1.5 plug i found one at car quest for less then 3 bucks
Good info, thanks!

Smaay
03-10-2009, 11:00 PM
ok now here is the big question, on the ODBII cars, how do you prevent the CEL from coming on?

I know in the Supra world they plug a resistor in the VSV plugs. i dont see any reason we cant do the same. anyone want to chime in?

also on my supra, instead of using block off plates, i actually tapped the hole in the head and intake manifold and put a below flush plug in, then bolted the EGR stuff back on, so it looks like its there, but does nothing. since i have my engine out, ill take pics of the 5S-FE withthe EGR off and add here for ya.

grayscale
03-10-2009, 11:10 PM
I'm guessing you mean for your 7gC. Not sure but it makes sense, see if you can find out the resistance it shows on the 2ZZ and try it.

More pics are welcome. I know a few others have done the same thing so pics of that would be very useful.
Thanks Smaay!

Luni
03-10-2009, 11:51 PM
AHA!

ZZ engines dont have EGRs. They dont need em with their VVTi

grayscale
03-11-2009, 03:07 AM
Well there you have it folks! Thanks boss! :bigthumbu


Smaay- what were you referring to?

grayscale
03-11-2009, 03:10 AM
AHA!

ZZ engines dont have EGRs. They dont need em with their VVTi
Curious, how does VVTi cut down on NOx and HCl?

taibones
03-11-2009, 03:17 AM
http://www.acehardwareoutlet.com/(wlo4bg553n3eof55ykt0me45)/productdetails.aspx?sku=2147006678&source=GoogleBase

i know ace hardware has them to

MrWOT
03-11-2009, 03:23 AM
Curious, how does VVTi cut down on NOx and HCl?

You intentionally cause reversion via overlap.

Smaay
03-11-2009, 09:53 PM
Well there you have it folks! Thanks boss! :bigthumbu


Smaay- what were you referring to?

i was referring to my 6th gen 5S-FTE

grayscale
03-11-2009, 10:22 PM
So the egr system is tied into the ecu? Up until 96 they were just mechanical so there's no problem with those.

Smaay
03-12-2009, 07:51 PM
well there are VSV's with plugs in them. Supras are the same way. and the EGR looks almost identical. so im expecting a similar result. my 6th gen is throwing a CEL for EGR not flowing already so im just going to block it off and try the resistor route. let me find the supraforums thread

Smaay
03-12-2009, 09:21 PM
http://www.mkiv.com/techarticles/no_egr/

http://www.supraforums.com/forum/showthread.php?t=199972&highlight=egr+removal

Smaay
03-13-2009, 01:31 AM
Pix added!

grayscale
03-13-2009, 01:38 AM
Mind if I use some of those up top?

Smaay
03-14-2009, 01:59 AM
use what up top?

grayscale
03-14-2009, 02:23 AM
Your pictures.

Smaay
03-15-2009, 05:25 PM
oh duh, of course thats what i posted them for.

grayscale
04-06-2009, 09:52 PM
the nut that goes in the back of the head is a m18 x 1.5 plug i found one at car quest for less then 3 bucks
Does that go directly into the head or is it a cap that goes over the threaded bit sticking out?

presure2
04-09-2009, 11:57 PM
the union bolt that sticks out of the head is removable, and just fyi, a tranny fill/drain bolt fits as a block off bolt perfectly.

grayscale
04-10-2009, 12:00 AM
Yep, confirmed, thanks!

presure2
04-10-2009, 11:04 PM
the union bolt that threads into the head:

http://i9.photobucket.com/albums/a57/presure2/IMG_0521Medium.jpg

and the tranny fill/drain bolt bolted onto the head.

http://i9.photobucket.com/albums/a57/presure2/IMG_0520Medium.jpg

http://i9.photobucket.com/albums/a57/presure2/IMG_0519Medium.jpg

grayscale
04-10-2009, 11:34 PM
Nice pics dude, thanks!

presure2
04-12-2009, 10:57 PM
Nice pics dude, thanks!
np man, once i fab the block off plate for the valve itself ill post a pic of that as well.

Simonhla
05-11-2009, 07:37 PM
So can I just confirm that I can use a tranny bolt in place of a block off plate? If not where can I get a plate? I tried a few sites but no luck. Can I just JBweld a coin over the hole at the back?

I'm guessing this is all pretty obvious to most others but it's rocket science to me.

ciento44
05-11-2009, 07:45 PM
So can I just confirm that I can use a tranny bolt in place of a block off plate? If not where can I get a plate? I tried a few sites but no luck. Can I just JBweld a coin over the hole at the back?

I'm guessing this is all pretty obvious to most others but it's rocket science to me.

The block off plate goes in the intake manifold. It's not threaded. JB welding a coin would work, just be careful.

The bolt is for the head.

ciento44
05-11-2009, 07:47 PM
Dumb question, though....

What's the easiest way to get that damn union bolt off without removing your entire intake manifold?

Freshnicity
05-11-2009, 09:07 PM
Dumb question, though....

What's the easiest way to get that damn union bolt off without removing your entire intake manifold?

Unbolt the TB, an break it with an adjustable. How I did it. Do work son.

ciento44
05-11-2009, 09:08 PM
I guess i need to scare up a smaller adjustable.... the old 2 footer isn't quite cutting it.

Shadowlife25
05-11-2009, 10:50 PM
Ben, I have been in your garage, you have what you need. It's the Crescent Wrench with the green handle. Same one I used to do mine while I was there.

ciento44
05-12-2009, 03:14 PM
Ben, I have been in your garage, you have what you need. It's the Crescent Wrench with the green handle. Same one I used to do mine while I was there.


Yep, i can use that to get the line out of the union bolt, but without taking that whole side of the engine bay apart, it ain't getting to the actual union bolt to take it out. Even the resident hero mechanic couldn't do it with that tool.

Why did you take your union bolt out?

presure2
05-12-2009, 08:20 PM
crap, i never posted a pic of the block off plate i made.
its just a strip of aluminum i had laying 'round the garage that i trimmed and sanded to fit with a cut off wheel and a sanding disk on my 90* die grinder, then drilled the holes.

http://i9.photobucket.com/albums/a57/presure2/IMG_0580Medium.jpg

DaneDog311
04-11-2010, 11:31 PM
anyone have specs for the block off plate? I'd like to make one prior to removal... or can i buy a billet one somewhere first?

I'll take some b4 and after pics