What advantages to removing the EGR? - PeachParts Mercedes-Benz Forum

jbach36 · #1 12-06-2008, 09:08 PM

What is the EGR, what does it do, why is it there, should I remove it, why, and what advantages of removing (or disconnecting) it?

Does removing it reduce noise? I heard it reduces or eliminates gunk in the crossover tube, but how does that help me?

jeff 1991 300d, 127k

TheDon · #2 12-06-2008, 09:13 PM

when the gunk turns rock hard and falls off into the intake valve then into the engine we'll talk

Actros617 · #3 12-06-2008, 09:16 PM

removing the egr is a must because the egr will clog up the intake manifold, it also increase the cylinder head temp to give a little bit more power and better gas mpg usually increases up to 1-3 mpg more

Jeremy5848 · #4 12-06-2008, 09:45 PM

There are pictures on this forum showing intake manifolds nearly clogged with a mixture of oil and soot from the EGR, an extreme condition but possible. Most people (including me with 3 diesel Benzes relieved of their EGRs) see little or no improvement in either performance or fuel economy.

compu_85 · #5 12-06-2008, 10:42 PM

On your 91 2.5 you're going to have the trick the computer to keep the turbo going

(The 3.5 engines have no checks for the egr like the 2.5

)

-Jason

sixto · #6 12-07-2008, 01:30 AM

Philosophically, it's not the advantage of removing EGR as much as the penalty for keeping EGR.

Sixto
87 300D

dkveuro · #7 12-07-2008, 01:47 AM

Quote:

Originally Posted by jbach36

What is the EGR, what does it do, why is it there, should I remove it, why, and what advantages of removing (or disconnecting) it?

Does removing it reduce noise? I heard it reduces or eliminates gunk in the crossover tube, but how does that help me?

jeff 1991 300d, 127k

Do you really not know, or is this a rhetorical question....well I suppose it could hardly be rhetorical in the context of a forum question...so anyway....you know why it was installed by Mercedes, yes ?

Coming up to date though, the VW TDi's I work on all get the EGR flow reduced to minimums so the intake will not plug up with exhaust gas cooked blow by engine oil.

Some of them arrive here and are so plugged that 50 mph is max' speed.
I think IIRC, that in many states, disabling the emission equipment on a vehicle used on the public highways is a Federal offense with fines and black helicopters.

It's use (EGR.) is to reduce oxides of nitrogen...a photochemical pollutant.
Side effects are reduced power, if too much EGR flow allowed and carbon build up in the system and intake including the back of the intake valves.

On the plus side it cools the combustion gases by diluting them with spent gas from the exhaust. VW used to use a cooler and a filter on the 1970 thro' 1976 up T1/2 and T3 air cooled engines. Later T4 engines needed it in the buses to stop detonation too as well as pollution control....a California initiated regulation....hence the California compliant as opposed to the 48 state compliant smog labeling .

If you Google EGR there's tons of info available. Removing/disabling it is dependent on your compliance with local and state law and smog check requirements.

Federal Law forbids alteration or removal. ( I believe this statement applies to automotive tech's only.)Check your states smog regulations.

Anyone wanna chime in with more details.?

.

GregoryV022 · #8 12-07-2008, 01:57 AM

the EGR system was a attempt by Mercedes to clean up their diesel's exhaust fumes. didn't work very well. we know now that the reason for the dirty exhaust was high sulfur content of American diesel. EGR onlly has a significant effect of large diesel engines, like the the one ins container ships. but those burn fuel oil. not really diesel. so unless you plan on installing a 5 story tall powerplant in you car. disconnect the EGR

dkveuro · #9 12-07-2008, 02:16 AM

Quote:

Originally Posted by GregoryV022

the EGR system was a attempt by Mercedes to clean up their diesel's exhaust fumes. didn't work very well. we know now that the reason for the dirty exhaust was high sulfur content of American diesel. EGR onlly has a significant effect of large diesel engines, like the the one ins container ships. but those burn fuel oil. not really diesel. so unless you plan on installing a 5 story tall powerplant in you car. disconnect the EGR

Not to knock your post Greg' but, even the latest Cummins diesels are fitted with particulate traps and afterburners to clean up the exhaust even with electronic fuel delivery control even with this ULS fuel..

On a electronic controlled fuel system the ECU is programmed to read comparisons of EGR flow as compared to intake air flow and disconnecting it or disabling it will set a DTC and some will drop into limp mode if check sum is off on comparative data...

GregoryV022 · #10 12-07-2008, 02:33 AM

learn something new everyday. the old Mercedes diesel don't have an electronic fuel delivery or all those new gadgets. so the EGR doesn't get the job done efficiently.

compress ignite · #11 12-07-2008, 02:34 AM

jbach36,

http://www.peachparts.com/shopforum/showthread.php?t=212097&highlight=OM602+wastegate+swap

You Must read this Post,from end to end!
It is a long one...BUT All your questions are answered!

1.Free yourself from the EDS's enslavement of your Turbocharger.
2.Eliminate the source of "Crap" in your intake system!
3.Remove ,Once and For All,All three of the Electro/Vacuum transducer/actuator (s)!

dkveuro · #12 12-07-2008, 02:45 AM

Quote:

Originally Posted by GregoryV022

learn something new everyday. the old Mercedes diesel don't have an electronic fuel delivery or all those new gadgets. so the EGR doesn't get the job done efficiently.

Unfortunately the latest stuff don't get it done either to the satisfaction of the owners who are paying to have the intake cleaned on the 2006 up vehicles'

So far no one has been able to find a way to reduce EGR flow on the latest batch of vehicles from VW or Audi without problems. The PD fuel system seems to have a 'read only' program for the EGR. So unlike the up to 2004's we can't reduce EGR flow.

I have just serviced a 2005 PD equipped Jetta and the intake is clogging with EGR residue at 165,000 miles. I told him that a 200,000 miles it will be time for a top end overhaul. He puts around 300,000 miles on his car every 6 years.

If you drive like you stole it , it doesn't clog up, but he drives sedately everywhere.