Hi, I have a 2015 CLS63 AMG S and dissatisfied with a lag in throttle response during launch from a stand still and when slowing down and then re-accelerating. I almost killed my self taking a turn when traffic was coming because when I slowed to take the turn and then hit the gas there was literally a 2 second pause until the car started to kick. I had the pedal to the floor and nothing.... This is an ongoing dilemma and I am over it! Not sure if it is due to the MCT programming torque limiters to protect the drive train or just a poorly tuned stock ECU but it is beyond annoying. I got a CLS63 to have a monster engine with AWD but the AWD is not useful if the car does not kick hard off the line. It is honestly the weakest launch from a standstill that I have had in a performance GT car...WTF. I have contacted a few tuners and their answer to me was the lag is a know issue and a tune my help minimize it but not get rid of it totally...unacceptable answers to me.

My question for 2019 owners....How do you like the new 9 speed transmission? Any lag? How are the upshifts and downshifts in manual mode, comparable to DCT? Also how do you like the launch of your cars off the line...too much wheel spin? I love the look and electronics of the 2019 C63s AMG! It is literally the nicest looking BENZ to date IMO and I would consider getting one but I do not want to go in blind and be disappointed as I am with the CLS63. If it had AWD it would be a no brainer for me!!!

Thanks in advance for any help or advice.

LF

I can tell you the shifts aren't as snappy as I'd expect, especially if you try to double shift. Granted, I just got done with the break in so I haven't pushed too hard in Sport or Sport +. I also haven't done any hard launches but even a mildly aggressive launch gets wheel chirp.

ive had mine about 4 months. Adore the car in almost every way. I enjoy the 9 MCT, though took some getting used to coming off a 7 sp manual in my C7 Vette.

I haven’t launched with the paddles - no need to. The car leaps off the line in auto. The rear will let loose on you if you smash the throttle, but the transmission is really responsive and I’ve noticed no lag. It does a surprisingly good job of downshifting with rev matching so a quick decel then getting on it again is smooth quick and the car just goes! I found myself in a potentially bad situation wher I deciding gunning it to get out of there was my best option and it performed flawlessly. No lag in the gears or the turbo. I was outta there!

Back to manual: I do use it sometimes to upshift when in S+ mode and the car thinks I’m trying to be more aggressive than I really am. Shifts are smooth and immediate. I’ve downshifted two-3 gears once or twice and no complaints there, either.

Ok, thanks for your feedback!

Ok, great to hear you are loving your car! I had a 2017 Charger Hellcat prior to my CLS63 and getting traction was almost impossible at low speeds when you get on the pedal. This is why I was so happy to get an AWD car with high horsepower. The performance off the line and the lag at low speeds is virtually a deal breaker for me. I am considering trying an ECU tune and changing out the pedal to see if that helps. I really love the CLS63 but I cannot live with this constant lag and weak off the line performance. Thanks for explaining your experience and enjoy the car. It is literally one of the nicest looking cars I have seen in a long time!!!

Get a Sprint Booster. You will see a difference in responsiveness.

I've driven a 2016 CLS63 several times, and the only time I felt anything like you're describing was when the car was still in Comfort mode. Once out of that mode, the car had next to no lag.

If that isn't the case, it sounds like there is something wrong with your specific car, not the design of the car.

Yes I have read others have done that...just does not give me a warm and fuzzy to have to do this. I may give it a try though. Thanks!

LF

Maybe you are right??...but there seems to be many threads about people having the same experience with the same engine as mine (M157) on the E63 forum. Also I spoke to two different tuners, Renntech and Eurocharged, and both told me this is a common complaint. This is why I assumed it was a common issue and not just my car. I suppose I will take it to my shop and get it checked out first. My tech told me sometimes the pedals go bad and replacing the pedal helps decrease the delay. Thanks for your help and reply!

LF

The trans lag with the M157 and 7 MCT is the same problem I had in my 2014 E63. The cars can't launch bc of TQ and power cut in 1st gear. You're gonna have traction problems in the C63, even though the 7 MCt in the prefacelift was improved over the 2014 M157 models, the 9MCT is still not going to help you put power down.

What you need is the W213 E63.

Lol...you are not the first person to tell me to move forward to the W213. I considered it but I just purchased the 2015 CLS63 about 8 months ago-ish and put carbon fiber exterior pieces, new wheels, added Android auto module, etc... I hate to dump the car now and take such a loss. I think maybe a sprint booster or pedal box may fix my issue combined with a good tune from what I have been reading.

Can't believe they have not come out with a C63s 4matic. That will be hands down the best combination but I believe MB will be worried it would decrease all the other 63 sales? I can't think of any other reason they will not make the C63 AWD. Apparently the M4 will be AWD in 2020...at least that is the rumor I read. MB will have to up the game to compete so maybe after that happens??? We shall see. Thanks for your reply.

LF

I had experienced several times the situation you described in my 2017 C63S, and they all happen in comfort mode, once switch to S S+ or Race, the throttle response is much faster. Guess it's just the mode

Unfortunately not on mine, I always drive in S+ and I have had it happen in all modes including M. Thanks.

LF

Don't get me wrong, there is a bit of turbo lag. But having a delay like you're describing isn't normal.

The only thing I can think of is that ESP is kicking in and cutting power. I've had that happen to me many times when ESP is fully enabled.