jctevere

I have contacted MBUSA, through emails, genbenz, mbadvisors. They are purposefully NOT answering the question. Lol. They will answer and respond to posts both above and below my question on this issue, but not this issue itself. And I have tried this twice...

Perhaps they don't know yet (the people I have asked) and are waiting for information on it. But the first time I asked was back in October 2011, and again early january. So I doubt it takes that long for answers...

My guess, nothing special, just "good design" that helps minimize carbon buildup. Or whatever they try to feed. It might not have bad carbon buildup like other manufacturers, but definitely not the best solution. My guess is needing a rehaul/clean out every 75k - 100k miles...

kevink2

4 year 50K warranty?
.

RLE

Now, there's a great source for real technical information.

RLE

Why would you think they will tell you anything? If anything could ever be called proprietary, this is it. Admitting to anything and revealing what they are doing to fix it, would be blabbed all over the net immediately, just like you want to do.

Since VW, MB, Porsche, Isuzu and and all the others have been selling DI-engine cars for some years now and have been promoting the very real advantages of DI, you can be certain that all of the engineering departments have been burning the midnight oil trying to come up with an answer that doesn't cost a fortune or damage their reputations, whatever they may be.

And don't forget warranty costs when these engines have to be repaired. MB for one learned that lesson the hard way with the ML oil debacle.

nyca

When you see dealers offering the "DI fuel system cleaning package" for these cars, you'll know what to do.

jctevere

I definitely see where you are coming from, but I believe there is a way of crowd control statements that will not expose any secretive or proprietary designs/information.

Would I like the in-depth details of exactly why I shouldn't have to worry about it - yes. But I would certainly settle and be happy with something like, "We have extensively tested and made modifications/design changes to the engines to help combat this issue to the point where it is a non-issue" - or at least something to that effect.

Besides, when the car is sold public, their technology becomes public knowledge, as you can bet your bottom dollar that at least one is being bought by competitors to strip down and examine (and I'm sure this goes the other way).

kevink2

Sorry, but I missed the many contributing posts from you on my thread.

alsyli

Agreed. Several of us actually OWN the car. I think it's a good thing that we're deeply invested in making sure our cars run as well as possible for as long as possible (in terms of keeping long-term costs down and protecting resale value).

I'm assuming that non-answer you received is more about the potential for a lawsuit (should something go awry) than it is about any type of proprietary technology (at least in the US.... I'm assuming car manfacturer can sort of reverse engineer the design from other auto makes?).

As for manufacturers rigorously testing things to make sure they don't damage their reputations.... I'd like to think this occurs, but how about the SBC brake system on the SL- and E-classes? The brakes worked just fine objectively but were so subjectively awful (at least for the first year) that MB decided to drop them from the old E-class (I'm not familiar w/ the oil problems you mention from the ML). Or even the i-drive from BMW (although everyone ended up copying that).

I think people who post on social forums are probably a slightly different population than the vast majority of people who walk into a dealership to just buy a car....

MBRedux

RLE

The point was that asking a Mercedes salesman about technical subjects along these lines is a waste of time.

RLE

I'm glad you brought that up. I too own my C300.

If I was driving a car on a two year lease I wouldn't care one way or another.

MBRedux

Sadly it's starting to look as if MBenz dropped the ball with this one and are about to follow in the disastrous footsteps of their fellow German competitors. I don't wish to be the bringer of bad news, but I recently got off the phone with Mercedes Technical in NJ/USA. After speaking with several subordinates, I finally received a call back from a senior technical representative... this was his response to the questions and fears we all have with their latest Direct Injected engines and the infamous carbon issues which have plagued their competitors who converted to this technology much earlier than they did and now find themselves being hit with massive class-action lawsuits.

His Technical response:


I nearly crapped in my pants I was laughing so hard. Clearly this generic response wasn't written by an engineer, or anyone who truly understood how this technology works! In fairness I asked if there was some integrated engineering that went into these new engines that would aid in the reduction of carbon build-up.... adding that they haven't had any reports of carbon build-up because these brand-new engines haven't been on the road long enough! He said he was "not aware of any additional technology" (such as Dual Injectors, EGR and PCV rerouting, oil separators, valve guide improvements, etc) in these new engines.

Well there you go.... I would have thought if they indeed had addressed this carbon issue during the design and engineering phase, it would have been front and center with a proper response for all those smart enough to ask.

It's not there, they have no answer and that scares me. They have NO satisfactory response to a simple question which makes me think they didn't do anything to address this HUGE problem and are hoping that it doesn't jump up and bite them! Yikes! That's sad Mercedes!

I would be very skeptical and cautious about buying these new DI engines from Mercedes... and I have two on order! We're rethinking it as I type.

2012c350

That SUCKS! It's nearly enough to make me cancel my order. It just might...
Curious what needs to be done to clean the intake for a DIYer? Wonder how many people will blow up their engine while its under warranty to get a fresh one ;-)

nlpamg

Wow. Good to know. Glad I'm not keeping the C250 past warranty.

The Porsche DI engine that Glyn posted was absolutely stunning... Terrible.

MBRedux

The issue isn't about "blowing up" your engine. It's the opposite, the engine grows old real fast...slows down and gets sluggish. Over time, somewhere between 20K-50K miles, DI engines start feeling sluggish with severe hesitation, loss of power, etc. Then as the miles pile on the condition gradually worsens.

This process is accelerated yes, but it still so gradual that most manufactures of DI engines are betting that the average daily driver won't even notice it until the warranty has expired.

Audi wasn't so lucky though and they along with their parent, VW, are in deep doodoo. (If you were to look, we own two VAG autos, a new GTI and an Audi Q5, both with DI carbon issues, and we don't need two more!

We cancelled our orders until such time we know otherwise or Mercedes has proven that these NEW DI engines will be free from this carbon issue.

2012c350

The "blowing up" comment was tongue in cheek. I was saying that people who know about the issue will intentionally sabotage the engine just before the warranty expires in hopes of getting a new engine...thereby giving them another 40K of non Carbon issues.

But it appears that most MB owners don't keep their cars long enough to care. And I believe that MB knows that and is why they released the engine without addressing the issue.

> We cancelled our orders.
I'm assuming that cleaning the intake isn't tough, so I'll likely keep my order and just clean it when the time comes. That's the plan for now...

Glyn M Ruck

High mileage is expected of Benz cars in ROW. They have not experienced trouble on previous DI models sold from 2003 onwards in Europe - e.g W203 C200 CGI.

2012c350

> People - please don't go running after a problem that we don't know exists with Benz.

>I'll get an answer. In the not too distant future I hope.

>There will be no further comment from me on this issue....I suggest you ask Benz
>directly. I'm sure you will find their comments reassuring...Let them comment directly.

From MBRedux: His (Benz directly) Technical response:





>High mileage is expected of Benz cars in ROW. They have not >experienced trouble on previous DI models sold from 2003 onwards in
>Europe

Glyn, you certainly know your stuff, but your tap dancing around this issue and stating facts that don't directly address the topic...a topic that you specifically stated you won't address, is more reason for the rest of us to suspect that there is indeed a serious issue. It appears to me that either you don't know the answer and are just being overly optimistic, or you do know the (bad) answer and are too close to it to address it. Neither of which is comforting. You stated "contact them directly"...and MBRedux did. So the only real answer "we've" received from MB is not good.

nyca

Perhaps the intake rail has a fitting for a DIY cleaner in a can? Or at least, a service the dealer can perform every 30K miles or so for some reasonable price. The bottom line is, I don't think you can expect this to be a service free item on these DI engines, notably for owners who keep the car.

MBRedux

Unfortunately Seafoam is proven to be a hoax... so even if there were "a fitting" it wouldn't work. The ONLY way to clean carbon build-up is to either remove both heads and have them dipped or blasted clean using walnut shells, or remove the intake manifold, mask off the engine bay and car, and blast each individual intake port with the same walnut shell blaster making sure both intake valves are closed as you proceed down the row. Then reassembling the engine.... around $3500 - $4,000 bucks!... ouch!

SSJ

Im sorry everyone I dont know anything about the motors of MB I have just been following this thread after I bought a c180 CGI couple months ago.

I dont want to be selfish but all I can read about the DI Carbon is related to the 3.5 liter or something or did I misread something?

Does this problem presents all CGI motors?

MBRedux

This issue concerns the latest & newest 1.8L DI and 3.5L DI engines for 2012.

RLE

Walnut shell blasters have been around for decades. I have had the procedure done on two cars in the eighties when the gasoline producers removed the detergents to save money which turned into a huge problem. One was my MB 190E under warranty and the other my Porsche 944 (both port injection, not DI) which I paid for since Porsche denied there was a problem, naturally. The Porsche felt like it gained 15hp overnight after the carbon was gone.

Yes, the intake manifold is removed.

Then a flanged 2-way divided hose is bolted to each intake port and the machine, powered by shop air, is turned on and a directed blast of walnut shells is aimed at the carbon buildups removing them in short order. The hose is then moved to the next intake port and so on. The used shells and carbon schmutz are simultaneously sucked out by the other half of the hose and expelled into the blaster's holding tank. The whole operation is contained in the hose so there is no masking of anything.

The cost for the Porsche's cleanup was a few hundred dollars but keep in mind how long ago this was. Probably a few hours labor.

MBRedux

Yes, they have been around and will continue to be as long as the internal gasoline combustion engine is around I guess. Yes dual active blasters do both missions simultaneously, but some newer models (read as less expensive versions) require an assistant holding the vacuum right next to the blaster nipple. Either way it works great! But today's newer engines are put together without those good old gaskets of yesteryear, they now use siliconized gasket material and sealants all over the place, plus it's a freaking mess to get the manifold off these days because of motorized port flaps, sensitive sensors, all kinds of servo's and a slew of other PITA doodads! Then if you do this procedure with the heads still on the engine you will need to rotate the engine by hand in order to guarantee the intake valves are completely closed for each cylinder before the port/valves are blasted clean or you will fill up your cylinder cavity requiring the heads to be pulled.

At my shop I do mask off the car we're working on... our blaster does get nasty at times and my high-end clients really appreciate the extra effort.

That how we do it in my Nismo Tuning Shop anyways.... just my 2cents!

kevink2

First, it has not been confirmed there is a DI build-up problem yet, but no assurance from Mercedes that there is not a problem.

.