pokerFACE

http://ca.autoblog.com/2012/06/11/20...-v6/#continued

superangrypenguin

And this is precisely the reason I just bought a brand new C300 4matic in Canada (fully loaded). <--2012 model with port injection

I had a 2007 Audi A4 with direct injection, great car, loved it, but the direct injection was killing the poor thing. Even with 5000km oil changes with German Castrol, engine oil was being sheared down to a high 20 weight after 1500km (yes I did a UOA). Knowing my car was choking itself to death even though I'd WOT every once in a while was a constant nag. Everyone's seen how bad DI kills engines (With the exception of Lexus's port/DI setup).

I wish the mainstream media would tell people how bad DI is for NA (b/c of our dirty fuel = no stratified injection) and how carbon buildup ruins engines in a few years (or a few $ in cleanings)

MBRedux

There appears to be no carbon issues with Mercedes' new DI engines. https://mbworld.org/forums/c-class-w...n-buildup.html

schvamf

Now the question is what will it take to undo the "de-tune", hopefully just a chip

Domm

Give Mercedes more credit for craftiness

Stevedotmil

The intake from the 350 and a tune should do it.

LandSeaAir

That would be amazing if you could chip the car and get the power of the 350. Among performance enthusiasts, It would probably turn into one of the best bargains out there.

MBRedux

Wish this was the case, but I fear its much more I heard. It will entail a new intake, flow sensor, whole new ECU, (not just a chip or firmware flash), plus the higher lift camshafts as well! My source wasn't completely sure, but he says there's a chance that the heads are different as well, (larger ports (maybe polished) and valves). He's the chief regional Benz tech rep for my district, who just happens to be a customer of mine. I looked into this because we just purchased a brand-new 2012 C-300 Sport 4-Matic. We wanted the new DI 3.5L but they're not available in 4-Matic which is necessary in our family because we are avid skiers. Because of that disappointment, we were thinking of trading up to the detuned 2013 C-300 4-Matic 3.5L and retuning the car up to full spec in my shop. But his answer is making me think otherwise, not very cost effective.

Why doesn't MB just bring over the C350 4-Matic damn it!

Glyn M Ruck

MBRedux ~ all this crap is being driven by European emissions standards. First they chased NOx, then CO & now CO2.

MBRedux

I don't understand your comment pertaining to this subject matter? Designing two engine configurations for a specific model line, one with more power than the other but using the same block, isn't new and has little, if anything, to do with chasing emissions.

Glyn M Ruck

The lower powered unit has far better emissions. Benz is detuning/retuning engines for the sake of emissions & dropping capacity where they can & turbo charging.

http://ec.europa.eu/clima/news/artic...1062901_en.htm

2012c350

Please explain how a poor DI system causes oil breakdown.

MBRedux

Got it! I stand corrected... but it sounds like wasted effort... typical though.

Glyn M Ruck

Yeah! They have to look across the entire production fleet now in Europe similar to the old CAFE (Corporate average fuel economy) standards in the US.

Not encouraging for those that want performance. AMG has stated that they will not neuter their cars power wise but will capacity wise. Benz is going to have to achieve the savings mainly across the rest of the fleet.

BMW is in the same boat with the 6 cylinder engine being reserved for the 335i as an example in the 3 Series. The 328i is now a turbo 4 banger & while it's a good 4 banger it simply does not have the character (and great sound) of the 6.

MBNUT1

The real question is what will be the fuel mileage? I'm hoping that it will be better than the E350 4matic which is pretty good.

Glyn M Ruck

Fuel consumption will be lower. Has to be.

MBNUT1

Lower than the E350 4matic or current C300 4matic? If you are referring to the E350 I would wonder how the gearing and the Cd would play into it

MBRedux

Fully agree. BMW and others have adopted the "Auto Start/Stop Function" to get around our CAFE standards. Test drove one recently. Hated it!

ElJayBird

This makes no sense at all to me. Can you explain precisely how DI will "kill" a car??

Glyn M Ruck

Both.

DI can cause inlet system fouling. It has absolutely nothing to do with oil shear - zilch!

kevink2

Not sure of how reliable this is:

consumerguideauto howstuffworks 2013-mercedes-benz-c-class

"This premium-compact car comes as a 2-door coupe or 4-door sedan. Either body style is available with rear- or all-wheel drive."

but for sedans, is contradicted by:

"The rear-drive C350 Sport coupe and sedan, along with an all-wheel-drive C350 coupe, use a 3.5-liter V6 engine that is rated at 302 horsepower."

but this looks good:

"Special-order options include the Dynamic Handling Package for C250 and C350 models."



So this article suggests more options vs 2012 models, I think? But no mention of the special de-tuned 350 engine for the C300 4MATIC.

.

MBRedux

From what I understand, the engine line-up for the MY2013 in the USA will be: (Excluding 6.3 AMG's)

C Coupe = 3.5L DI rear drive / 1.8L DI rear drive / 3.5L Fully Tuned DI 4-Matic

C Sedan = 3.5L DI rear drive / 1.8L DI rear drive / 3.5L Detuned DI 4-Matic (& sold as a C300 4Matic)

Go figure?????? Just bring over the Sedan the same way as the Coupe!

superangrypenguin

Hey guys,

Sorry, hadn't had this thread stickied. To answer a few questions that were asked...

I had a 2.0T FSI from Audi. Any Google search will reveal tons of intake valve issues and tons of "fuel dilution" in engine oil issues. So what essentially happens is that the cars run VERY rich and cannot enter stratified injection due to the low gasoline quality in N. America. In Europe, the FSI engines can run incredibly lean leading to very little blowby with the cylinder rings. In N. America, they cannot - they constantly run very rich and some fuel eventually makes it past the cylinder rings. This fuel then contaminates the oil, slowly reducing it's flashpoint until the oil becomes volatile.

The fuel does eventually burn off as its flashpoint is quite low, but the damage is done. The oil vapors eventually make their way back through the system (PCV system) to be burned off. This cakes the intake valves and we see a reduction in HP. As gasoline does not hit the back of the intake valves (for the Audi design), the valves get all covered in carbon. This leads to eventual misfires, cold start issues, and degraded HP performance.

There are several cases of Audi RS4 which are hit INCREDIBLY hard. Some users report ~5000 mile issues. I got mine up to 97000km without problems by doing 4500-5000KM oil changes, constant used oil analysis reports and by using German Castrol (Or 0w30).

Now, you want proof, so let me give you some. This is my UOA:
http://i140.photobucket.com/albums/r34/saaber1/oil.png

What you see from the fuel dilution is that after only 2750 miles, my oil had sheared from a high 30 weight (almost 40 in the case of GC) to a 20 weight. That's...insane. If you look up UOA's of the tried and tested C300 after 10000 miles, the flashpoint is still around 385F and TR levels of fuel dilution. This would mean an increased probability of more intake valve caking. You may wonder why we just don't tune our engines to run stratified injection like in Europe, but the answer is the NoX levels. If we run stratified injection, our NoX levels would be above EPA recos.

I cannot speak to the MB design, from what you guys have said you have not had issues with DI engines in the C250 and C350. But I tell you, as an Audi owner, it was painful, always wondering about when you'll misfire and why your car feels slower. I loved the car, lots of good memories in many cities, but everyday when I drove it, I just felt like it was slowly dying.

As far as the new 2.0T TSI engines, they apparently raised the engine temp by 10F (hearsay), and the new PCV system is apparently better. I can say the supercharged engines are pretty clean now, but the new TSI motors in the Q5 have the same issue (Google...)

I have a belief that marketers are at play here. We want to increase MPG, reduce N and CO, while increasing HP. The problem now is that while these new DI engines are awesome, they don't stay awesome and so we end up causing more environmental issues with dead engines in an earlier time. Some automakers have found the sweet spot though (Lexus with their D4A?) with direct injection when you WOT, and indirect injection in low-med throttle apps. The new 1.8T TSI engine in Europe that will make its way over here with the B9 A4 (2014), will feature indirect and direct injection as well.

Happy to answer any other questions...but that in a nutshell is what I learned in 4 years

MBRedux

Please see above.

VAG's Solution: This Dual set-up will slowly encompass VAG's entire engine line-up.



Notice The Benz Set Up! Far Superior than VAG's initial DI design. The injector location/timing overlap is a simple remedy and appears to be working on MB DI engines.




PS: BTW, Catch-Cans do not help, regardless of what the advertisers says on Audizine or Vortex.

superangrypenguin

Where does Mercedes stand with their DI applications? Are they really spot-free and do they run rich causing fuel dilution as well?