Hi folks,

Apologies for the not so perfect English (it isn't my native language).
My E63s 2018 has entered "dummy mode" few days ago and all workshops are helpless, incl. the official MB dealer. While being on the highway, I noticed a change in the exhaust sound and noted a very serious loss in power and boost (like 320hp on the dash) and hardly reaching half on the boost meter. Took it next day to my workshop and my mechanic - Xentry is clean, no error codes, nothing.
The exhaust sound has changed to a much deeper one, with much more pronounced rumble, very close to my GLE63s with M157 engine (more bass, more clear V8 rumble) - far away from the normal sound of M177.
Tried everything - checked the exhaust valves and they seems to work just fine (although with squeaking sounds, which was new to me), the vacuum to the turbo gates is working super fine (the valves are holding it, no vacuum leaks), the transducer valve gives 0.8 vacuum on the meter (0.85 is the max according to the tech. doc), but it still lacks power and sounds like the engine is running on 6 cylinders. No misfire codes, nothing - Xentry check is clean like a baby.
My mechanic is helpless and so are 2 other workshops + the official MB/AMG dealer - they said we see no error codes, we can't do much and the car seems fast...Tired of people who work on things they just don't feel and don't like. 🤯🙄

Any ideas will be much appreciated!

Cheers,
Alex

P.S. For my peace of mind, I ordered a new vacuum lines and a new solenoid valve, although mine seems to be perfectly fine.

 

Anyone?
Spoke to another "premium" workshop, focused on performance cars and they guessed it might be due to a melted / broken catalytic converter(s). But the temps of both are absolutely identical.
Feeling lost. 🤷‍♂️

 

is this car under warranty - and if so benz has abandoned you in trying to solve this? And if so then it's a lemon and consider pursuing that route

 

I suggest to try a few other MB dealers in your local area.

 

Thanks for chiming in here. That's for sure, but first will inspect the catalytic converters for damage tomorrow.

 

It is your exhaust valves. They sometimes do not throw a code but will restrict power usually at 4000rpm and above. Leaving you with 300-400BHP on a 4600lb car
When the valves go, the CPC restricts power

 

https://mbworld.org/how-tos/a/merced...g-power-388450

here are something to check …

 

This is likely it imo.

If you need a fix for it contact these guys :

https://instagram.com/efb_adaptors?igshid=YmMyMTA2M2Y=

 

I've also been quite sure it is the exhaust flaps, but 3 workshops checked them and the actuators seems to move freely, the flaps in the rear mufflers are also moving from opened to closed (but with squeaky sounds while moving). We have also tested the actuators individually via Xentry - both seems to work. No error codes. Not sure that I know what CPC is though.
What's quite weird is that despite Xentry gives you the option to control the left and right actuators separately, both flaps are closing and opening regardless of whether you're testing the left or the right actuator. 🤯🤷‍♂️ I was thinking one of them should be the "master" or so.
Been thinking to install Acrapovic cat-back titanium exhaust, but haven't pulled the trigger for this yet - it is quite pricey and I'm not even sure the exhaust flaps is the real problem now...

Thanks for posting this - I've seen this thread earlier - these guys are doing great job. Will send them a message to find out whether they're shipping to the EU. Do you've an idea about the pricing of these adaptors?

 

I don't know the pricing but they're local to me and a number of guys have fixed their car with their parts. I was actually just talking with them and they were saying if your scanner can't read the cpc then it won't show the thrown codes for the flaps either. They said toss them a message and they'd be happy to help and explain.

 

Thanks, will drop them a message now.
I don't have my own scanner - my workshop is also an official MB partner, thus - they're using the original "Xentry" system, provided by Mercedes-Benz and it should read everything, which is allowed from the manufacturer (most of the diagnostics and updates are happening online via direct connection to the servers in Germany).
Just for the sake of curiosity - can you advise what the CPC stands from?

 

Central Powertrain Controller Module

 

For the statics - problem solved.

It was due to a melted/broken left pre-cat (upper one, behind the turbo). It got broken into small pieces, hitting also the main cat down below and damaging it.
During the inspection we noticed the right pre-cat also started to break, so I decided to replace the two downpipes. Bought the OEM ones, mostly because I was unable to find any performance downpipes for this car in stock and all the tuners asked for 1 month lead time. It is weird to see that the OEM downpipes are like twice cheaper than, say, Supersprint with 200 cells cats on them. The former has 4 cats in total, while the Supersprint has only 2 (1 per side) and the latter is twice more expensive.

Thanks to all who helped.
Alex

 

Why didn't it throw a code with the O2 sensors if a cat was damaged.

 

That's a very good question that only Mercedes can answer. Furthermore, while the left pre-cat was simply missing (broken into pieces), the right one was still there, BUT the temps of both O2 sensors behind them were showing exactly the same temps, which is simply ridiculous.
While speaking to my senior engineers and mechanics at the local AMG dealer, they said this isn't something new to them - more often than not the M177s won't throw error codes for broken/melted cats, nor cracked intakes. They also said most of the AMGs, driven with Shell V-Power racing 100 have melted their cats and these cars should be driven with 98 RON, which is really hard to find across EU (everything moved to 100 RON). 🤷‍♂️🤯 I've been using mostly Shell VP Racing 100...
That's it.

 

Interesting, I was going to make a post on it. Looking at an 18 e63 US. And found it had the intake manifold replaced.was hoping is wasn't an oddball issue just with this car I'm looking into. Ha

Is it common for these to Crack on the m177s. From heat or am I totally wrong ? Haven't seen many.

 

^It happens, but this isn't a common issue as far as I'm aware.

 

Ok, here we go with another update - after replacing the broken cat(s) with brand new, genuine downpipes (both left & right), the car has been flying for... something like two-three weeks and today it happened again - same issue, same drama. Melted/broken cat(s). Will open again the connection behind the turbo chargers to inspect and if this is the case, I'm giving up with AMG and going the M5 or RS6/7 route for sure and won't look back. Already sold my GLE63s.
MB/AMG must address the quality, reliability & dependability as a top priority - they need it urgently.
Cheers!

 

I'm kinda experiencing the same issue on my 2018 E63s, I was wondering it could be the flaps since I got the car a couple of months back, got a RENNTech EVM and when I went to install it>? left rear flap was unplugged, plugged it back in and then everyday after being stationary for a while, the flaps would make a squeaky sound when I unlock the car. I had someone unlock it for me so I could see from a closeup myself, and it seemed that there is something preventing the flaps from moving more than a couple of millimeters, sometimes they would open and the exhaust would sound more aggressive than other days. I threw in downpipes and ended up replacing the exhaust with an aftermarket valved exhaust hoping this could solve the issue but it did not since the exhaust had proprietary valves harness, so what I did was, removed all the actuators from the old exhaust and connected them to the stock wiring harness and tucked them near there, no improvements. Got the car tuned and the downpipe CEL light went away, had more torque but HP limited to 320-360 at most, Boost would go past half only when not pushing the throttle too much only enough for it to build good pressure. Eventually I disconnected all 3 actuators to see if it got any better and no luck, I was told by the tuner that after I get it CPC tuned it would put down all the targeted power. He told me after he tuned it and there was no power increase since I thought a CPC tune was only required for 2019+ models stated in several popular tuning websites But since I just got the car 3 months ago and have already put a lot of money into it, besides grabbing a CPC tune for it what other options are there so I can get it to at least 600 HP? Thanks.

 

??? The 2018 E63S is rated at 603hp stock.

 

Exactly, but that’s what I’m trying to figure out; what is causing the car to only push out 360 hp.

 

Whomever tuned it should a least be able to come up with some plausible reasons why it isn't producing any power.

 

My intake diverter valve was leaking and car would struggle to keep boot . Seems to be good after changing it . Worth a shot changing it.