Tvall13

1st gear from stop. ESP on, suspension sport, engine race, manual gearbox


just like the other videos I don't get full boost well really ever it seems but peak isn't till 4,000

Tvall13

Yes all of these videos are pedal to the floor in slow motion

jkob5

yeah that doesnt look right, my car has been tuned for a while now but I definitely had full boost earlier than that

Maybe pu the car on the dyno for objective evidence the car is not meeting advertised numbers.

AlexZTuned

Yup, that definitely doesn't seem right... unless boost is cutting off or ramping up slowly because of ESP/traction, it should not be that slow to spool.

I think whoever mentioned the pinched wastegate vac line is giving sound advice. Definitely schedule an appointment with MB and get it checked out... I think it's just a coincidence that you started having these issues after the update.

ezatnova

how can it be a coincidence when numerous people have the EXACT same issue IMMEDIATELY after picking up the car from the dealer to get this update.

The issue is the update.

auditoamg

I think it could be triggered by the update, but have a physical manifestation.
In other words, the updates changed a parameter something in our cars can't handle.

J.M.G.

I tend to disagree with most statements in this thread.

1. This car is a 500hp car, but it is also a 4.0 Liter car! Therefore it has torque like a 4.0 Liter car, up to the point, where the turbos deliver full boost. A BMW 4.0 NA V8 (M60) had approximately 300 Nm (220 ft lb) at 1,000 rpm. So I do absolutely understand, that this car is not a beast without boost!

2. The turbos on this car are huge. When the car is going from coasting load to full load, those turbines have to spool up. This takes some time, as the turbine is exhaust gas driven - so you need exhaust gas! The higher the RPM, the faster the spool up. The car DOES give you full boost at 1,750 rpm. Just select manual mode, choose 5th gear and 1,500 rpm and floor it - you will see the boost build up! You will not see that in first gear, as it takes longer to build up that boost, than revving the engine!

Note: do that again at the same speed but shift down to 4th / 3rd / 2nd! You will clearly see that the boost will build up faster the higher engine rpms are, when going from coast to full load.

3. Regarding the "hot V": Mercedes-AMG does not advertise that it had been chosen for less turbo lag. They claim that the engine is more compact in this setup and can be used in a wider range of vehicles.

ezatnova

So your car has the same issues described here? When did you get the exhaust update?

Bottom line is that the car is night and day after getting the software update. I wouldn't make excuses for the post-update performance given that the car used to be a beast and now is "meh".

AlexZTuned

So when are you bringing your car in to the dealer?

Tvall13

Well the ESP kicks in at around 4,250 in the 1st gear video so that cuts the boost. 2nd gear video ESP you can see never kicks in and therefore I don't believe it is the reason for the boost being so slow to spool.

Pinched wastegate vac line could be an issue but rather interesting a few other people have had this exact same problem right after the update. That being said the car was already at the dealer and they claimed the couldn't find anything wrong with it and that they compared it to a new car and it felt "normal".

The dealer is following up with me after I talked to the service manager and they will be letting me test drive a new C63s Cabrio to compare. Either way in a car with peak torque starting at 1,750 you shouldn't have to wait until 3,500 for full boost. If you watch the videos I have NO boost at peak torque RPM and it doesn't start spooling at all until around 2,500.

J.M.G.

It takes less than 3 seconds to go through first gear from a stop. In my opinion, it is impossible what some of you guys expect. The turbine needs exhaust flow to spool up (and to overcome inertia). This can not be done at low RPMs in 3 seconds. The very good 3.0 I6 TwinTurbo from BMW (N54), that used a lot less boost, took way longer to spool up from coasting load to fuel load in a stationary test at 1,500 rpm.

What you notice might be an increased traction management. The wet clutch had been updated as well.

gasman213

This is my first post and I have just received a C63s coupe 3 weeks ago. Had the update done 1 week ago and would not call my car neutered but definitely different. When i back out of my driveway and go backwards up an incline, I have to give it more gas before it moves and there is a point where the car does not move til I build revs above 2k. I am wondering if the "neutered" throttle has to do with the clutch being recalibrated to help with rough shifts?

ezatnova

TCU was updated as part of this so the clutch behavior could have a part to play here as well. I don't think it's purely a boost thing.

I was shaking my head on my drive out at lunch time today. From a stop, making a 90° turn, I mashed the throttle and the car just casually took the turn. Before this update, the ESC would have been going nuts, or if in Sport ESC, I'd have a nice controlled slide I could counter correct. Nothing like that anymore.

gasman213

I am sorry to hear that. My car definitely feels slower to launch but just as beastly once I hit the right RPM but what u describe sounds pretty extreme and maybe something else is up. I will keep an eye on this thread forsure. I am sending my ECU to eurocharged so Ill let you know how my car behaves after tuning.

L8apexer

A brand new 3-week-old car should have the latest software from the factory and does not need an update. This is of course moot if you bought a used car. Please clarify.

gasman213

build date was 8/2016

auditoamg

Sorry man, the car reports from the manufacturer claim full TORQUE, not boost necessarily, is available at 1750RPMs.
How does this align with what you just said?
Further, my car feels way different.
Period.

auditoamg

The car is reported at 0-60 in 3.8 seconds.
3 seconds in first sounds like you have an issue there, as well.
Being as my car would literally pin me to a seat almost immediately without jamming the throttle before, and now I have to jam the throttle to get even half of what a 40% or so throttle depression provided, it's clearly an issue.

PaulE550

Interesting thread. If the problem occurred after the firmware update, why can't the dealership's service department just back out the updated firmware code from your ECU or over-write the new code with the previous version code that was in your vehicle? Thus putting the car back to a pre-update condition. It is just code after all and the ECU is just a special purpose computer. Kind of hard to believe MB can't do this simple procedure to test if the new firmware degrades the performance of a vehicle or if it conflicts in some way with other code on OP's ECU.

J.M.G.

Once again: Those torque values can only be achieved with full boost. In order to get full boost, the turbos have to spool up. The impeller is turbine-driven, which is exhaust gas driven. Therefore, your turbo needs exhaust gas to spool up. So when going from coast load to full load, it takes some time. Your car DOES offer you the advertised numbers at 1,750 rpm. Just try what I suggested (Manual Mode - 5th gear, 1,500 rpm, WOT).

I disagree. First of all: My English is not that good, but didn't I write "less than 3 seconds"? Also 3.Xs is very hard to achieve on the street with street tires. BUT - The most important thing is: At least my car uses second gear less than 2 seconds. In my opinion, you have the misconception, that all gears are being used for the same amount of time. In first gear, your car goes from idle through the complete rev-range. It also has to deal with traction issues. In second gear, the car just uses 5,500-7,000 rpm. This does NOT take 3 seconds. My car does the advertised 4.1s (0-62mph; C63S Estate) on the street with fully warmed tires. Most of the time it takes 4.5ish...


I do believe you, that your car felt different before the update. As -at least my car- still delivers the advertised numbers (torque AND 0-62mph), I just do not think, that the car lacks power. Instead of that, I would put my money into the off the line performance calibration... torque management AND clutch programming...

Tvall13

I think we are fighting over pointless aspects. The fact of the matter is the car feels slower, it spools slower, and power delivery is much less linear. I feel it in all gears in all speeds. I always drive in manual so i probably feel it more.

Before I spun tire by accident merging from a stop. Now i can't do it if i try. Also, at any speed any RPM in any gear i can mash the throttle and there is still some lag. While there was always SOME lag it was nearly unnoticeable before.

Also, I drove the C63s at the AMG Academy on the skid pad in 2nd gear going relatively slow. We would then pop the throttle to get the back end out. With the throttle response and turbo lag on my car I would not be able to do that. It doesn't have the same response that the AMG Academy cars did.

You can argue about how turbos will always have lag and that the videos prove nothing but the fact of the matter is that car feels significantly different to the few of us that are having this issue. The whole point of the video was to attempt to bring more objective data rather than subjective data. Clearly without a comparison video from beforehand it won't be able to prove anything. Unless someone takes the same video in a car they feel is unaffected or a car that has not had the update yet.

AlexZTuned

Just an FYI - manual mode on the Coupe actually changes the mapping so power delivery is more linear (for track use). Not saying that's the issue, but you get less boost/torque down low in manual mode than if you just floor it in auto.

I drive in manual mode 95% of the time and I've noticed the difference in power delivery.

Tvall13

While that doesn't make much sense to me and power delivery actually feels less liner than before, I did drive in auto mode in sport + and it did feel a bit more responsive. Granted before the update I only drove in manual mode and it felt way more responsive than it does now but maybe the update adjusted mapping in manual mode?

All I know is before the update I always drove in manual mode and it was super responsive and torquey. After the update I've always driven in manual mode and it's not nearly as responsive or torquey. In auto like you mentioned it does feel closer to how it felt before.

jkob5

any proof of this? I'm skeptic.

BallzOne

Ok here's my vid. Sorry, not the greatest video but it'll work for our purposes. Sport+, ESC on, automatic shifting. Comparing to yours it looks like we both end up in the same place coming out of 1st gear around 38mph. But my traction control kicks in before 3k. Are you using super sticky tires? I've got the stock Dunlop Sport Max RT on there.