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Discussion Starter #1
While re-assembly of the EGR valve housing I cracked it at the air intake side. My torque wrench was set for 13 ft-lbs (156 in-lbs), which is torque for the intake manifold bolts (EGR goes on the same intake bolts to the rear of the block). I did not even get the wrench to click when the housing snapped. I guess it was either crooked, or the wrench (my settings?) failed me.

Now, I will have to hunt the junk yards for replacements, I am sure Toyota has them, but they will charge me arm-and-leg for it.

EGR works by redirecting small amount of exhaust gases to intake. Exhaust gasses do not burn so the mixture becomes somewhat lean and cooler when burning. That controls the NO compounds. BTW, I previously failed NO emmisions, when I took the EGR housing off, I noticed it was 1/2 clogged with carbon deposits, hence it did not work properly. I am sure there were other reasons, too.

EGR is closed at cold start and at full throttle. It works in mid-rpm ranges.

If I cannot find one in the future I am considering playing with and electronic EGR from other vehicles and custom control it (autotronix project). For right now I might fabricate plates and close the ports and forego the EGR totally for a while.

If I forgo the EGR I am sure to fail emmisions and polute a little more, a bad, bad thing, but the engine should run until I can fabricate, or find replacement.

Finally, my Supra is the California edition, it has fuel temperature sensor in the EGR housing. It sends 0-5V signal to the computer by varying the resistance depending on the temprature. What happens at the computer I have no idea. Why the sensor is in the EGR housing not on the intake maifold I don't know. maybe I am confused.

Any comments, or sources of EGR housing parts, will be appreciated.
 
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Discussion Starter #5
Thanks guys!
I made two plates to cover exhaust and intake ports.
The shelf brakets available in any hardware store serve the purpose suficiently. Little cut-off wheel work and grinding and job is done.
Eventually, I will find a donor in the junk yard... time allowing to go and search, also access to the thing is not very easy with the cylinder head installed.

Thank you for the sale offer, I may just take you on it soon, but now I am not up to spending money at all if I don't have to.

I will track progress on:

http://supra88.blogspot.com/
 

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hmmm, california edition?
have pics of this said unit? or just look in the TSRM?
 
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Discussion Starter #9
<img src=http://homepage.mac.com/ukidlucas/.Pictures/Supra/EGR_126.jpg />

You can see broken housing on the intake side and extra sensor for California cars only.
 

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Mine broke in the same place- I just had it welded back on for $15.
 

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PS- Adding EGR gasses does not lean the mixture. If anything, it enrichens it. Adding Burnable gases (IE-Oxygen) would lean the mixture.
 
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Discussion Starter #13
hmm, I did not think about it - I considered cast iron welding as a no-no. I will give it a shot. Do you know what type of welder did they use? If it was steel or aluminium then it would be no brainer.
 
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Discussion Starter #14
Yes, to lean the mixture is to add oxygen, this is not the case here.

I meant to dilute the mixture so the burning temperature is lower.

The fuel intake should not increase, it should not enrich the mixture. EGR makes less burnable mixture flowing to the chamber.

I hope I got it clear and right...
 
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Discussion Starter #15
fatboy said:
:rolleyes: .....you live in IL, you will not fail emmisions, block it off I say!
I with fatboy too! if you don't need it don't fix it. :) BTW a new EGR from toyota is like 300
 
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