I've read about this before and think I'm going to try it. I'm curious as to how many people are doing this? What does EGR stand for anyway?


http://mbz.org/info/articles/engine/killegr.html

EGR = Exhaust Gas Recirculation and is done to lower the Nitrogen Oxide emissions. It's also very common on gas engines. Recycling the exhaust actually lowers the combustion temps slightly and contributes to lower NOX. Other than eliminating the soot that ultimately starts to clog the tube, I'm not sure you'll see much benefit in disconnecting this.

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LRG
1987 300D Turbo 175K
2006 Toyota Prius, efficent but no soul
1985 300 TDT(130K miles of trouble free motoring)now sold

What is the tube that comes off the valve cover and connects to the top of the air filter housing? What is it's purpose?

That's the breather hose that vents the crankcase vapors back into the intake so they are consumed by the engine. My '85 300 turbo vents these vapors both into the air cleaner center and also the intake to the turbo. It's another emissions device but in this case has the additional benefit of preventing an oily residue running down your engine by routing it back into the intake system.

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LRG
1987 300D Turbo 175K
2006 Toyota Prius, efficent but no soul
1985 300 TDT(130K miles of trouble free motoring)now sold

So in otherwords it's venting the blowby? Perhaps this creates additional cooling then.

That's right, it vents the blowby. I don't believe it cools any though, it's really just to burn up the vapors and avoid venting them to the atmosphere. As I understand it, the exhaust gases, because they are spent gases, very marginally slow down the combustion process and apparently just enough to reduce peak temp and reduce NOX production.

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LRG
1987 300D Turbo 175K
2006 Toyota Prius, efficent but no soul
1985 300 TDT(130K miles of trouble free motoring)now sold

turbodiesel,

Performing the EGR modification has yielded great benefits for me, and countless others with whom I have corresponded over the years.

The number 1 benefit is that the intake is kept MUCH cleaner, which directly helps to keep the banjo fitting more free of buildup so boost pressures are not compromised. The number 2 benefit is that by eliminating the introduction of exhaust gases into the intake, along with your cleaner air, turbo lag is greatly reduced and low-end acceleration is greatly improved.

Disclaimer: this is a modification of the emissions equipment and is not legal...I'll take my chances for a much cleaner, smoother operating engine.

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Chris

'04 ML500 - 53k, Inspiration Edition, Desert Silver
'11 Audi A4 Avant - Brilliant Black
'87 300SDL sold
'99 C280 Sport sold
'85 190E 2.3 sold

I'm not sure what is 'legal' in regards to EGR. My '84 euro 300TD has no EGR, but was imported successfully...now registered in California...by the way, if the EGR is disabled, it appears the vacuum switches on top of the valve cover would then have no function. I believe they remove EGR vacuum at idle and full throttle. These switches contribute to the various vacuum problems associated with the cars, as they age.

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D

I took out the top tube and could not detect any vacuum pressure while maipulating the throttle. So I gave it a test drive and it seemed to have a little more pep, but this could have been psychological. Do you have to plug the line or can you just leave it disconnected?

Plug the line - a simple vacuum cap will do.

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Chris

'04 ML500 - 53k, Inspiration Edition, Desert Silver
'11 Audi A4 Avant - Brilliant Black
'87 300SDL sold
'99 C280 Sport sold
'85 190E 2.3 sold

Is it normal then not to be able to detect any suction from the tube?

If the egr controller is telling the egr valve to open then you should have vacuum on the line. If not then, there will be no vacuum. Follow the line - you should come to a solenoid. You can leave it hooked up as long as you plug the line. You will lose vacuum when the solenoid cuts in otherwise.

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Jim

Greetings All,

I hate to chime in, but this topic always comes up to new turbo diesel owners about the EGR valve and the benefits / drawbacks of it's operation. I'm sure we won't have a tech respond to this, simply because it's against a mechanic's vows to cause harm to the ecology of the world, not to mention that there is probably a fine and removal of business license if they so suggested anything of the sort to us.
So for the rest of us that aren't in the field and have no license to lose. Is there someone out there that has had a plate made up to actually cover the egr port with the valve still in place, but no exhaust gases going to it? I could see removing the vacuum to the valve, but the valve will just accumulate soot from non use and it will eventually back up into the manifold. Tell me more about the performance you experience and some other methods for a permanent fix. If you feel uncomfortable posting them, feel free to use my email.

Thanks,

Charles

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"Tell me and I will listen, Teach me and I will learn, Show me and I will accomplish, Involve me and I will succeed."
'84 300SD 256,000 Gold on Brown (Mileage Award)
'86 300E 246,000 Blue on Tan