I just bought a 2013 CLS63 black on black, from a guy here in NC. said it was a "forum car" and was dynoed at 680 RWHP . So i'm trying to get some info on it and I'm new to the 218s..

When cold it shakes really bad in D or R off the line, regardless if in C,S,S+ or M (maybe a little less in C if you roll on slow).

I took it to the 1/8 drag strip just to see what it would run..i didn't want to mess with Race start on the line so I tried to build boost a bit (Brake+ gas) in S+ and when I released the brake it jerked so bad it stalled off the line!!!! (Never happened to me with a torque converter trans haha)! I started it back up and got into D (defaulted to Comfort and eco) got into it slowly then opened it up, and it still ran 98+ mph. .. A guy at the races took a look under the hood pointed at the back and stated/asked if I had an E85 tune to which I said "I have no idea.. I got the car 2 weeks ago" Overall embarrassing adventure.
I tried resetting the trans learning (car off, key in pos2 + pedal to floor, wait 10 sec, key to off, wait 2 min. it does seem to help a little bit.
iI feels like it lets revs build a little too high then grips a little too much causing rpm drop, then lets go of clutch, then revs high and so forth..

So I'm looking for any help on finding any info on what could be causing the excessive jerking when cold (it does get notably better when trans is hot) and any info on the car including how i would know if E85 is safe or tuned etc?

FYI
Car was listed with:
Blackboost intakes,
Blackboost downpipes
Eurocharged Orlando Dyno Tuned ( i called to get info but they had none in system from more than 3 yrs ago)
TSW wheels, front carbon spoiler, rear carbon spoiler, black vinyl on all trim, 0 level tint. etc.
Car also smells and sounds like cats are deleted but unverified)

Thanks for any help

 

Can't build boost with the factory TCU, you legit have half a second and it goes into a "limp mode" and falls on its face.

 

Limp mode from over boost or ..something else like trans etc.?
Can that be adjusted?
What is the best way to check if I already have a TCU tune?
Looking on top of engine I just found an aftermarket ethanol content analyzer and extra fuel lines etc

 

^^^^this

likely you experienced a protective mechanism in the mct trans that doesn't allow brake boosting past 1500 or so and not for more than a second or two. This would be normal behavior for your car

get a tcu tune and you'll be able to launch better, just make sure you realize a tcu and hard launching will shorten the life of your output shaft (prolly about 100 hard launches before it shatters) given the car is already old and has been tuned for a while.

you cannot adjust your stock tcu
go To eurocharged and ask for the EDOK tcu tune
you don't have a tcu tune, it would have been a selling point by the previous owner and your launching issues speak to the fact that you have a stock tcu

btw what did the guy see under the hood that indicated you have an e85 tune? An in-line fuel sensor? Are you running e40 mix or did you fill up with 93 octane?

Consider using this for reference during your ownership:

https://mbworld.org/forums/w212-amg/...-w212-amg.html

 

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Thanks for the great info! not 100% on the TCU because I'm beginning to think the previous owner didn't know everything about the car because I found the undisclosed ethanol content meter (made by Spool, linked below) Yes the guy at the track was pointing at what i know see is the filter and meter (no efuels, I've only filled it with 93 (one tank since bought) I downloaded the Spool app as it's apparently a wireless transmitter but the app apparently has a bug per the fault message when i try to start it).

Would still like to solve the trans shaking issue when just normal driving.

https://euroklasse.com/products/spoo...saAnd8EALw_wcB

 

I'd personally figure out the tune first. If you have a dedicated EC E30/E40 tune and you're running 93 it could cause some serious damage. If you have a flex fuel tune, you'd be fine. I think doing some data logging would be your best bet. A transmission service wouldn't hurt either as you don't have the service history. As mentioned above it doesn't sound like you have a TCU tune or you wouldn't run into the "falling on its face" when trying to brake boost off launch.

I have a very similar set up in my 2012, I trap 99mph in the 1/8th - 128-130mph in the 1/4 with a 93 tune.

 

You have a big problem if you are using 93 octane and it is running a tune that requires 30% or 40% E85 fuel. These e tunes to my understanding do not do a flex feature, they're either one percentage, or another percentage or one type of octane or another type of octane, there's not a flex capability, such as what you see in stock, Chevrolet vehicles, for instance. Your issues in normal driving could entirely be that you're not using the appropriate mix but I would expect you to see some check engine lights, have you checked the car for codes?

 

Very familiar with the spool sensor

 

Have you ever driven a car with a multi clutch transmission from Mercedes? The MCT transmission is notorious for spooking new owners because it drives like a poorly driven stick shift car. It feels like it bucks and it jerks when you're trying to accelerate slowly or come to a stop at a stop, sign and accelerate again. This is a well discussed nuance of this particular transmission and eventually you'll learn how to use your foot the right way to learn the proper technique to accelerate and to re accelerate once you slow down.

If you think that this is still abnormal behavior beyond what the traditional feel of and MCT transmission is, then you may need a readaptation of your MCT wet clutch, and this is extensively discussed in the sticky that a link to you, too, or you may need someone to look at your transmission in terms of clutch packs, and a more specific proper readaptation at the dealer

Also, did you get a PPI before you bought this car? Did someone go through and check fluid levels such as transmission, fluid levels, and all the other pertinent things you consider doing before buying a high-performance car like this?

 

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Unfortunately I didn't get a pre purchase inspection, I had talked to a Mercedes tech I know after first test drive, he convinced me since it was tuned and had mods etc that the dealer checks wouldn't help much.? it only has 57k on it. Only code scan it's got since i got it was getting the NC state pre-registration inspection, where they plug in to OBD and look for recent erased codes etc. (found nothing) I don't have any dash lights or messages on either.

The previous owner also stated that it had just gotten:
oil change with liquid moly
a trans service
New OEM plugs,
Brake fluid flush

I just called Spool also and he recommended I put 3 Gallons of E85 into a full tank of premium and see if it wakes up helps (stated it wouldn't hurt eitherway). I'm curious if the car is fighting itself between knock sensor retardation and advanced Ethanol tune timing and injection.

About to call the shop he had it at last to get as much info as i can.

 

You should be getting codes registering if knock, usually; if you're driving well high in the rpms and no issues then this is unlikely a knock issue. Starting off shuddering is the mct trans or wet clutch

Your car may be ok, but my opinion is that a tuned car is highly needy of a good inspection, a ppi is usually an independent inspection well beyond routine dealer checks, and this would be from someone doing a ppi who has a good rep

There are e85 mix calculator apps for your smartphone you can use to start

Read up on the mct and see if this may be your issue

 

I've read up a little on the MCT and it does sound like the issue is common (i need to dig further into the info linked earlier) but regardless I feel like it's a bit excessive sometimes, I've gotten better at minimizing it will the throttle but seems crazy they let these off the lot like this.
I feel adding the 3 gallons of E85 is a low risk thing to do given the ethanol sensor hardware. Too bad the Spool app doens't work on my phone Grr. (i did get an android screen to update the oem screen) hopefully I can load it on that to work.

Where /how would one find a reputable inspector for a tuned car like this?

 

google "pre purchase inspection ________" filling your area of the US/Canada in the blank or do same on Yelp.

the 2010-2013 mct's were not as smooth as subsequent mct's.... a sprint booster like I have can greatly help the bucking of the mct .. super cheap at $300

 

Eurocharged Orlando are second to none if you are having an issue with a car they tuned my first call would be to them. You may need to reflash or they can walk you through the issue over the phone. If your in FL it would be worth a drive to go see them.

 

Thx ! I did call them but unfortunately they couldn't find a record in their system, stating they only go back 3 yrs.. (was likely done before)

I did manage to get the ethanol detector linked up, and I tried adding 3g of e85 to a tank of 93 (per Spool tech). Definitely didn't help the jerking any and didn't feel or notice any significant hp gains, (hard to tell on public roads and it was wet for a few days.. so I topped up with more 93 and its sitting at about 17% E right now based on spool sensor.

the jerking will even begin the moment you get off the brake sometimes, (even before you get your foot to the gas pedal). And it actually stalled on me once at a stop sign .. just normal driving.. shortly after a startup on a 66deg day..

 

Maybe an mct readaptation can help; or you have bigger mct wet clutch issues

 

Adaptation seems like next step.
don't think I'm having any other wet clutch issues.. any hints or signs on what might present ?(sorry if this is already covered somewhere else in forum, which I'm sure it is)

also FYI I was able to get a copy of the last work/ inspection done. Previous owner was trouble shooting same thing. They did a trans service (fluid) as first step before attempting adaptation then i bought.
Didn't note anything else serious otherwise (swapped dirty brake fluid, and engine oil, small oil leak from cover found, torn swaybar link boot).

 

you could have a bad valve body ... that's more surgery on your trans though

hints of bad wet clutch - poor engagement off the line such as no idle forward advance on flat surface or stuttering into forward motion

see my sticky and review mct adaptation

 

Many thanks for the info!
definitely no issue with forwarding motion on level ground etc.. I will read up more and likely try the adaptation asap.