begone

So, we just got out car back from the dealer - we were having issues with the car putting itself into park when the Start/Stop would engage - and it became dangerous as cars would expect us to take off at the stop sign or stop light and the car was in park (almost got rear ended) - but it wouldn't let us just put in drive - we would have to turn off the key and then turn on. Apparently it was a battery modulator of some sort that monitored the battery charge...anyways, it seems to be fixed.

But after I picked up the car, I noticed something strange. Not only did it seem underpowered, it also would feel as if it bounced off the rev limiter and pulled power. You know that feeling. But I wasn't in manual mode - I was just getting on it getting on the freeway. So tonight I took it on the highway and you can see where it almost stalls out, and then re-engages...it's only at higher speeds so I can only get it to do it higher up on the revs. Check out the video. Any idea what that may be?

Skizz

No idea about the issue, but wonder where you can do 130 mph while filming your dash

fabbrisd1

Frankly - your Owner's Manual or a Salesperson with AMG expereince..

1. Let's get directly to your "issue" - you need to know your AMG:

Mercedes-AMG vehicles: the automatic transmission does not shift up automatically
even when the engine limiting speed for the current gear is reached.

When the engine limiting speed is reached, the fuel supply is cut to prevent the engine from overrevving. Always make sure that the engine speed does notreach the red area of the tachometer. There is otherwise a risk of engine damage.

To shift up: pull steering wheel paddle shifter ;.The automatic transmission shifts up to the next gear.

2. You really should note the break-in instructions - sure, everybody gooses their new rig a few times - but since you don't know - how many times have you pushed to fuel cutoff - see breakin below...

"The more you look after the engine when it is new, the more satisfied you will be with its performance in the future.

You should therefore drive at varying vehicle and engine speeds for the first 1000 miles
(1500 km).

Avoid heavy loads, e.g. driving at full throttle, during this period.

Change gear in good time, before the tachometer needle is 2/3rd of the way to the red area of the tachometer.

Do not manually shift to a lower gear to brake the vehicle.

Try to avoid depressing the accelerator pedal beyond the point of resistance (kickdown).

Additional breaking-in notes for Mercedes-AMG vehicles:

Do not drive faster than 85 mph (140 km/h) for the first 1,000 miles (1,500 km).

Only allow the engine to reach a maximum engine speed of 4,500 rpm briefly.

Change gear in good time.

Ideally, for the first 1,000 miles (1,500 km), drive in the Comfort drive program.

After 1000 miles (1500 km), you can increase the engine speed gradually and accelerate the vehicle to full speed.

-----------------------------------------

Keep the beat !

begone

I'm well over 1000 miles. Also, this was all done in auto mode and I was not manually shifting.

gobiman

Looks to me like a speed limiter - European cars generally have them at 155 mph.
If you were supplied with all-season tyres in the US market, I think I read somewhere that the there was a 130 mph limit due to the speed rating on the tyres.
Also have a look in the menu - there is the ability to add a "winter tyre" speed restriction - maybe it's on inadvertently?

begone

Nah man you're not watching the vid. It stalls around 118 mph and drops back down to 116 and then picks back up again and goes to 130.

begone

It's just did it again with my wife around 60 mph

ble2716

Bad gas?

vikeor

THats something you get from an old taco.

dejongj

That or a fault. I would take it in.

ble2716

Yes, same symptoms.
Lots of bad gas and "crap" out.

Agree.

Witch

I would have it towed in with that kind of issue.

begone

I'm taking it in on Monday. Not sure if it's Gas - the transmission is acting really wonky. It shift points are all over the place, coming from a stop it slams into gear, it think its transmission related.

begone

Just got word from dealer...needs new transmission. So bummed. Also, they haven't even addressed the loss in power.

So I got a brand new GLC43 and drove it back to back with mine and with the technician in the car and he and I felt the massive loss on power. So I'm dealing with a Bad Transmission AND bad turbos or engine or just a Bad Transmission. Either way car is out for the the next few weeks. Sucks. Bad.

Mr. J

It is not a new model engine. This engine has been in production for since early 2015 and detuned variants existed before that. Transmission problems would easily explain the loss of power whereas an engine issue does not jibe with the evidence from your video.

I hope it gets worked out to your satisfaction quickly.

dejongj

Good result Told you to take it in

I don't agree with your conclusion though, the car has been out since 2015, the engine has been around for a long time as well. The transmission is used in nearly every other model. Failures just happen unfortunately, just think about it, if they didn't happen there wouldn't be any garages

begone

You guys are right. I've adjusted my post as I don't want to put out false info. I really hope the new transmission will fix the issues and power issues. We will see in the next 2-3 weeks. Dealer says 8-9 days to ship tranny, and then I'm sure another week to install and make sure everything is working properly.

begone

Just got word Transmission won't be here till March 18th. This is such a shame. They dropped the Transmission pan and it was full of shaved metal flakes.

They are hoping this is why the power wasn't getting put to the ground, but won't know till they install the new transmission. Sucks.

Skizz

I assume you are quoting this out of the manual. Could you please point me to where it is? I looked through the manual for my '43 and for the life of me I could not find this info. Thanks.

davideldg231

What’s the update? Did the transmission fix the issue?