I was doing research because I want to do the same mod as you guys and I was so lucky to find this thread.
I have few questions.
1) Which KTAG did you guys used? The one with red PCB? It was working right out of the box or some rework was necessary on the PCB?.
2) How's the engine temperature after you deleted EGR? From my research deleting EGR will increase combustion temperature. Did you notice any difference?
3) How's the odor in cabin? It is very bad or it is ok? Are there any cons on the DPF/EGR/SCR delete you noticed?

I'm about to this, thanks so much ccrobin for your assistance with this post and the encouragement.

question, does anyone know if the SCR/DPF have to be removed?
can they stay on at least temporarily?

thanks

If you remove the SCR/DPR before reprogramming the ECU, you will go into limp mode. Program the ECU first if you cannot do both at the same time - though I cannot comment on any problems created by driving with a tuned ECU and leaving the SCR/DPF in place. I know others have done it for short periods without issue.

Curious to know what the new average, improved (lower), fuel consumption is over a period of 3 to 4 months and whether that improvement is attributable mostly to the re-tuning of the ECU or mostly because no fuel is being used for the DPF regeneration.

Also, I believe with some systems (Green Diesel Engineering for instance) the reprogramming (re-tuning) is done through the OBDII port which should be much easier to do than to access and open the ECU. Am I missing something?

Did you noticed increased RPM when idle? Today I loaded the tune to my car and RPM when idle is around 760, before the tune it was around 600.

Headed down this path right now. My ECU is in OR being flashed right now. And I have the two Buzzken pipes in my garage right now. After reading a few posts it looks like there are two paths to take. One remove just the DPF filter and leave the muffler in. Or two use both Buzzken pipes and delete both of those. Which route did you take? I also noticed neither delete pipes have a port for an o2 sensor???

well I am probably just going to hollow out the DPF, as there is no "pipe" being sold for the E-Class. The GL Still has the DPF on for now, need to get around and fixing that soon. Right now it just that the adblue delete, and got it to pass inspection. the heater was out, the tune got rid of it.

Also for some reason on the tune I got, torque limiter had to be be turned off in the ECU, as it was going in to limp mode. but now its running great

yeah I agree thanks for this thread. I found a video on YouTube explaining Diesel SCR system. Where I was wrong was thinking that the Adblue fluid was sprayed in front of the DPF... it doesn’t it is after and there is a Nox Catalst (SCR) and Adblue is sprayed before that.

the BuzzKen pipes replace both the DPF and SCR...

I’m right in the middle of removing both of them now.... I’ll take pics as I go. I already have both upper and lower clamps removed.

I removed both. Some want to leave the Catalytic converter in place to help with the odor. Problem is it is also prone to getting Clogged up. While I notice an odor standing directly by the exhaust pipes when running, it is not noticeable any other time so I am glad I replaced both.

yeah I’m under it right now. I’m going with your advice and I’m ditching the Cat.

Any wisdom on access to the to small hardline pipes that go into the DPF filter that goes up the the pressure sensor? I’m at that point right now and the DPF is out...

I got it from underneath just behind the front passenger side tire. Long wrench (maybe even a pipe over it) to get the leverage to bust em free. once you break them loose you can remove with your fingers.

Trick is to get it jacked up a bit. Be sure to use jack stands! You don’t want that heavy pig falling on top of you.

Ok I’m going in, I’ll spray them with Penetrating oil and give it a shot.

Watch the knuckles. When they break loose your hand is going to go flying.

The lower hard line is off. That upper one is going to take strategizing.... went to check the upper area and found this...




And this...
That first seal was just loose in there and the other seal at the inlet of the Turbo doesn’t appear right...

I’ll deal with turbo seals after that DPF pressure line. Do you remember how you accessed that upper line?

Bill, from where you order the ECU tune?

I used the same guy ccrobin used

Ill probably leave as is for now, eventually going with a high flow diesel cat. at least that is the plan. we have inspection here, most guys wont check, it passed with the tune, but dont want to fail a visual, want to look as stock as possible

Sorry, been away for a few days. Did you have success with the upper line? For me it was just a bunch of swearing and stretching that got it.

Does you tune force set the monitors? Otherwise it wont pass an obd check for emissions.

I ended up removing the right side air cleaner box and it was right there in the clear. I unplugged the pressure sensor and just removed the sensor completely.

After a few months I am consistently getting about 32 MPG on the freeway at 75 MPH.

As to the OBDII programming, it depends upon the ECU, Not many support this level of programming via the OBDII port. Many you can program by the connection pins on the ECU module itself (which requires puling the ECU), and unfortunately the ECUs in a 2012 GL350 require the ECU case to be cracked open as there is 1 pad on the mainboard inside the ECU you need to connect in order to program. It sounds daunting, but really not that bad.

I would not recommend this if you are in an area that requires emissions checks. You are sure to fail.

Thank you for that information. My vehicle is pre-Adblue and the DPF regeneration is not giving any trouble. I was curious to get an idea of how much fuel is burnt and lost in the DPF regeneration process.