EGR Block plate for 97 E300D - PeachParts Mercedes-Benz Forum

97E300D · #1 10-31-2003, 11:13 AM

I would like to install a plate or SS washer without the hole it, to block Exhaust from entering the intake manifold, while leaving the EGR valve free to open an close.

I have 2 questions:

Will any sensors detect the lack of exhaust gas and effect performance, or throw a Code ?

Does eliminating the exhaust gas from re-combustion and hence raising the combustion temp, effect engine reliability?

I what to keep the intake clean after the mess I found earlier.

Thanks,

shoe · #2 10-31-2003, 11:50 AM

I do not have the answers to your questions, but I can relate to your distaste of the crud that is deposited in the intake from the EGR valve. I had the intake off of my 96E300D and I was amazed as to the amount of sludge. Thankfully it had not turned hard as is the case in a gas burner. I could not imagine trying to chisle that stuff off of an aluminumum intake and head. I would suspect that the computer would not throw a code becaule it only reads whether the valve is open or closed. as far as performance I would be curious about that. How many miles do you ahve n your 97, and have you had much trouble with it?

97E300D · #3 10-31-2003, 12:18 PM

The Car has 67K. By the looks of things you are way ahead of me by some 200,000. That is impressive to say the least........ What your secret?

I have long wanted a diesel Benz, nearly picked up an 80's 300D a few times, last month traded our 02 VW TDI in on this one. After about 3 weeks I started to get the common 96-97 surging problem. This forum gave me the info to correct the problem. I would love do away with build up in the intake and keep the "resonance flaps" free.

I have read on the TDi forum about higher combustion temps by blocking the EGR, but no one mentions the impact on engine reliability, hotter valves ect...

There is a temp sensor in the intake boot but this is before the EGR inlet, so shouldn’t detect the inlet air temp drop.

again WOW 274K on the 210, very nice.

mbdoc · #4 10-31-2003, 02:17 PM

YES, disconnecring & or blocking off EGR will cause a code and cause the IFI system to go into a "fixed" mode.

The EGR is designed to help with piston/combustion cooling.

97E300D · #5 10-31-2003, 02:44 PM

Thanks, M.B D.OC,
I've read your many posts and I respect and appreciate your all your help and expertise.

I think a regular maintance schedule would be the best solution. Any idea how expensive the Flaps are and where I could source them other then a dealer ?

I may try the SS Washer (with the hole) trick I heard about. There was a Fly buzzing around with this one.

Thanks again,

shoe · #6 10-31-2003, 08:23 PM

MBDOC, great info, By the way I believe the glow plugs took care of the CEL I have been plagued with. Been two weeks since it has come on. I too appreciate all the help you provide on this forum.

97300D, I actually bought the car with 274K on it. I now have close to 282K. the secret is to buy it form the owner of MB Autowerks so you know how the vehicle has been maintained. I had an 83 #00D with a couple hundred thousand miles on it it was fun too. This car is probably the best car I have ever owned. you should really enjoy it.

97E300D · #7 11-03-2003, 01:27 PM

M.B. DOC,
I hate to keep beating a dead horse, but I'm still curious as to "exactly" how the ECU would detect the following:

Keeping the EGR, it's wires and vacuum lines connected, attach a small air filter to EGR intake pipe, and block the exhaust from the down pipe. This would then allow the EGR valve to open and close letting in Fresh Air rather then exhaust into the intake manifold. Unless there are sensors which could detect the drop in temp or similar gas sensor to a O2 sensor it should work. I may be missing the obvious. I just hate the idea of clogging things up with this soot and goo.

Thanks

shoe · #8 11-03-2003, 05:25 PM

There is actually an intake air temp sensor just above the EGR valve. I do not know if it is that sensitive though.

psfred · #9 11-03-2003, 10:24 PM

I'm not sure how the computer detects the EGR valve operation, but I do know it is very difficult to "wire around". Just clean the intake as required and use synthetic oil.

A clean air intake for the EGR won't fool the computer, it's looking for a reduction in combustion temp.

Peter

97E300D · #10 11-04-2003, 09:52 AM

The Air temp sensor is up wind of the EGR intlet, at least it apears that way on the 97 E300.

If the senor reads the air temp before the EGR then fresh air through the EGR would not be detected ??? I'm not looking to to rewire or fool the system, just feed the erg fresh air rather then soot filled exaust.

97E300D · #11 11-05-2003, 01:58 PM

MB D.O.C.

Regarding the intake system and EGR function on the 96-97 E300

Could you please enlighten us on how the system works. This is turning into more of a thought experiment or lesson then anything. What is the logical chain of events that occurs. What sensors feed what information to the ECU and how does each system depend on the reading from each sensor. I also have to wonder if companies like "upsolute" make chips for 96-97 non turbo cars and if the ones for the 98-99 cars disable some or part of the egr process.

If you are willing to teach, we are surely willing to listen!

I have also remove all the flaps and throughly cleaned then. It is important to note that upon close inspection I could see where one of the flaps left marks on the manifold indicating a possible fluttering effect during a bind. I noted that thoroughly cleaning the area where the butterfly valves moved within the manifold was important. This ensured nothing would effect it's smooth operation. Problem is now solved but I'm interested in the process and like to tinker.

This is what I have read regarding the 96-97 606 engine.

A three-stage intake system on the E300 Diesel is the first ever incorporated into a production diesel automobile. It incorporates six intake runners feeding through a butterfly valve into a twin-pipe resonance manifold, which is divided by a second butterfly valve. The runners and resonance manifold lengths and volumes are tuned to give three torque peaks at 2,400, 2,900, and 4,000 rpm.

mbdoc · #12 11-05-2003, 03:38 PM

EGR system is monitored(constant) thru change of vacuum change in the intake manifold system.
The EGR valve itself is monitored thru it's sensor by voltage changes.

You are correct in the way that the intake runner length is varied for more HP in the upper range.

what is the engine doing?? What are you trying to fix?

97E300D · #13 11-05-2003, 04:23 PM

Nothing I fixed the stuck flap issue.

I'm merely interested in better understanding the how a system detects the actual EGR operation. And would like to make a Mod.

This is my what if "

Keeping the EGR, it's wires and vacuum lines connected, attach a small air filter to EGR intake pipe, and block the exhaust from the down pipe. This would then allow the EGR valve to open and close normally letting in Fresh Air rather then exhaust into the intake manifold. No change in Man Press, unless it can detect the ambient pressure as being different then that from the down pipe.

Unless there are sensors which could detect the drop in temp or a similar gas sensor to a O2 sensor, it should work. I may be missing the obvious. I just hate the idea of clogging things up with this soot and goo.

I do run Delvac1......

#14 11-05-2003, 10:49 PM

I couldn't believe that my 2002 TDI would throw a code when I disconnected and plugged the vacumn line to the EGR,
but it did, and when cleared, would do it again everytime.

So I must assume the same would happen to me on my '99 E-300 DT if I were to disconnect the EGR also?

97E300D · #15 11-06-2003, 01:07 AM

Nope, not disconnecting the EGR..........only feeding it fresh air.