2018 E63s feels like cutting boost or power around 3-4k rpm (no codes)
Thread Starter
Newbie
Joined: Sep 2025
Posts: 5
Likes: 1
2018 E63s feels like cutting boost or power around 3-4k rpm (no codes)
Hey all,
I have a 2018 E63S with around 96k miles. It drives perfectly normal at low speed. However, once under load (around 3-4k rpm) crackling sound from the exhaust comes out (close to what happens when you let off the gas in race mode), and a slight loss of power too on and off.
I hit a bump and I started getting a misfire, but once I reset the car it goes away. One of the times the misfire stayed and I had to replace a faulty coil as a code for cylinder 4 misfire came on.
After replacing the coil, the issue under load did not go away, and I got the misfire once again, but was able to reset the car and it went away.
There are no codes at all. the car does eventually give me the 600 hp, but it does feel a bit slower than before.
Please let me know if you have any theories or have seen something like this before on the W213 E63S
I have a 2018 E63S with around 96k miles. It drives perfectly normal at low speed. However, once under load (around 3-4k rpm) crackling sound from the exhaust comes out (close to what happens when you let off the gas in race mode), and a slight loss of power too on and off.
I hit a bump and I started getting a misfire, but once I reset the car it goes away. One of the times the misfire stayed and I had to replace a faulty coil as a code for cylinder 4 misfire came on.
After replacing the coil, the issue under load did not go away, and I got the misfire once again, but was able to reset the car and it went away.
There are no codes at all. the car does eventually give me the 600 hp, but it does feel a bit slower than before.
Please let me know if you have any theories or have seen something like this before on the W213 E63S
Out Of Control!!
Joined: Jun 2004
Posts: 13,799
Likes: 3,228
2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
Hey all,
I have a 2018 E63S with around 96k miles. It drives perfectly normal at low speed. However, once under load (around 3-4k rpm) crackling sound from the exhaust comes out (close to what happens when you let off the gas in race mode), and a slight loss of power too on and off.
I hit a bump and I started getting a misfire, but once I reset the car it goes away. One of the times the misfire stayed and I had to replace a faulty coil as a code for cylinder 4 misfire came on.
After replacing the coil, the issue under load did not go away, and I got the misfire once again, but was able to reset the car and it went away.
There are no codes at all. the car does eventually give me the 600 hp, but it does feel a bit slower than before.
Please let me know if you have any theories or have seen something like this before on the W213 E63S
I have a 2018 E63S with around 96k miles. It drives perfectly normal at low speed. However, once under load (around 3-4k rpm) crackling sound from the exhaust comes out (close to what happens when you let off the gas in race mode), and a slight loss of power too on and off.
I hit a bump and I started getting a misfire, but once I reset the car it goes away. One of the times the misfire stayed and I had to replace a faulty coil as a code for cylinder 4 misfire came on.
After replacing the coil, the issue under load did not go away, and I got the misfire once again, but was able to reset the car and it went away.
There are no codes at all. the car does eventually give me the 600 hp, but it does feel a bit slower than before.
Please let me know if you have any theories or have seen something like this before on the W213 E63S
https://mbworld.org/forums/w213-amg/...fixes-diy.html
Junior Member
Joined: Jul 2017
Posts: 46
Likes: 12
C63 AMG 2009
Like Cosworth2000 mentioned, spark plugs are a good starting point. At 96K miles, if the spark plugs have never been replaced, it would be a good maintenance job to start with.
I’ve worked on multiple cars with the M177 and M176 V8 engines , coil packs fail quite often. I also frequently see fuel injectors go bad and start leaking into the cylinders. When I replace injectors on these engines, I usually replace the whole bank, since injector replacement involves a lot of labor (around 5 hours per side).
If you’re looking for OEM injectors, I sell them for a fraction of the dealer’s price.
Let me know!
I’ve worked on multiple cars with the M177 and M176 V8 engines , coil packs fail quite often. I also frequently see fuel injectors go bad and start leaking into the cylinders. When I replace injectors on these engines, I usually replace the whole bank, since injector replacement involves a lot of labor (around 5 hours per side).
If you’re looking for OEM injectors, I sell them for a fraction of the dealer’s price.
Let me know!
MBWorld Fanatic!
Joined: Feb 2017
Posts: 2,296
Likes: 1,204
From: Baltimore County, MD
'13 s212 63 p30. '06 LX470
Hey all,
I have a 2018 E63S with around 96k miles. It drives perfectly normal at low speed. However, once under load (around 3-4k rpm) crackling sound from the exhaust comes out (close to what happens when you let off the gas in race mode), and a slight loss of power too on and off.
I hit a bump and I started getting a misfire, but once I reset the car it goes away. One of the times the misfire stayed and I had to replace a faulty coil as a code for cylinder 4 misfire came on.
After replacing the coil, the issue under load did not go away, and I got the misfire once again, but was able to reset the car and it went away.
There are no codes at all. the car does eventually give me the 600 hp, but it does feel a bit slower than before.
Please let me know if you have any theories or have seen something like this before on the W213 E63S
I have a 2018 E63S with around 96k miles. It drives perfectly normal at low speed. However, once under load (around 3-4k rpm) crackling sound from the exhaust comes out (close to what happens when you let off the gas in race mode), and a slight loss of power too on and off.
I hit a bump and I started getting a misfire, but once I reset the car it goes away. One of the times the misfire stayed and I had to replace a faulty coil as a code for cylinder 4 misfire came on.
After replacing the coil, the issue under load did not go away, and I got the misfire once again, but was able to reset the car and it went away.
There are no codes at all. the car does eventually give me the 600 hp, but it does feel a bit slower than before.
Please let me know if you have any theories or have seen something like this before on the W213 E63S
Sounds like you have a diagnostic tool? Have you run diagnostics on the fuel and ignition parts? If not, for the cost of one dealership visit (or less) you can buy a tool that will talk to and help diagnose every electrical part in the car as well as code or calibrate the new parts. And as echoed above, once one coil or plug or injector are bad, it is best practice to replace all of those parts at once since they have the same lifespan. The only time I dont follow that rule is if something fails very early in the life cycle, unless it was determined to be a batch issue. Lastly, you might want to drive a few cycles and see if the car readjusts now that it "may" be fixed. You do not want to ever drive with a bad injector as it will kill the engine and the best way to prevent against that is to use a high pea fuel cleaner once in a while and constant top tier fuels.
Newbie
Joined: Nov 2024
Posts: 2
Likes: 0
From: Chicago
2019 E300, 2013 CL550
I would definitely start with spark plugs looking at the mileage the car has, and you can find good ones from FCP Euro at a decent price. Then move to coil packs if the problem persists.
Thread Starter
Newbie
Joined: Sep 2025
Posts: 5
Likes: 1
Thanks for all the replies. I have changed all the sparkplugs around 10k miles ago. My main mistake was unfortunately both times a coil went bad i replaced the faulty coil only. This is because I cant afford the wait times for coils as they never had more than one in stock. I understand that is really not the way I should've done it and it ends up costing me more way on labor amongst other issues. I am thinking its something with the turbo system. The car revs fine while stopped but as I'm driving when it builds up boost, it starts to cut power and makes the popping sounds from the exhaust while under load (maybe cuts boost). I can definitely see it being injectors and i hope its not something worse. The car is getting diagnosed right now at a mechanic and I'll chime back in if he finds something.
Please let me know if you have any more suggestions.
Please let me know if you have any more suggestions.
Trending Topics
Out Of Control!!
Joined: Jun 2004
Posts: 13,799
Likes: 3,228
2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
Thanks for all the replies. I have changed all the sparkplugs around 10k miles ago. My main mistake was unfortunately both times a coil went bad i replaced the faulty coil only. This is because I cant afford the wait times for coils as they never had more than one in stock. I understand that is really not the way I should've done it and it ends up costing me more way on labor amongst other issues. I am thinking its something with the turbo system. The car revs fine while stopped but as I'm driving when it builds up boost, it starts to cut power and makes the popping sounds from the exhaust while under load (maybe cuts boost). I can definitely see it being injectors and i hope its not something worse. The car is getting diagnosed right now at a mechanic and I'll chime back in if he finds something.
Please let me know if you have any more suggestions.
Please let me know if you have any more suggestions.
You need a proper diagnosis and method. Someone who knows how to log the car while driving and making these pulls can determine many things about boost, wastegate duty cycles, fuel trims, o2, etc etc
surmising "I think it's the turbos" is understandable and just a guess - but you can narrow this down with a proper evaluation
driving it more risks catastrophic damage as mentioned above if indeed it is something like injectors .. these engines do not like misfires
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
Thread Starter
Newbie
Joined: Sep 2025
Posts: 5
Likes: 1
I definitely do not want to do a parts cannon with this. The mechanic is going to do a smoke test and a bunch of diagnostic. I will ask him log the car while driving if he wasn't planning to. Right now all I'm trying to do is maybe get some ideas for the mechanic so this doesn't turn into the horror stories I see on these forums. Where people spend months trying to diagnose a car and ending up having to sell.
Thanks again for you reply.
Thanks again for you reply.
Senior Member
Joined: Jun 2023
Posts: 425
Likes: 291
2018 AMG E63s Ed1
So E63s...
The first thing is...
check the exhaust flaps... a stuck exhaust flap will cause issues and depending on the car... might throw a DTC code.
Ignition on the E63s would be all the time. What you are describing reduces the probabilty of the plugs being bad.
Plugs either work or not.. there is no "works up to x rpm".
The first thing is...
check the exhaust flaps... a stuck exhaust flap will cause issues and depending on the car... might throw a DTC code.
Ignition on the E63s would be all the time. What you are describing reduces the probabilty of the plugs being bad.
Plugs either work or not.. there is no "works up to x rpm".
Thread Starter
Newbie
Joined: Sep 2025
Posts: 5
Likes: 1
I have gotten a flap code before and one the flaps makes a screech sound when i open it. The mechanic found a broken vacuum line connector on one of the turbos, so we'll see if that fixes it when he gets the part.
Out Of Control!!
Joined: Jun 2004
Posts: 13,799
Likes: 3,228
2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
several exhaust flap threads in the sticky
Thread Starter
Newbie
Joined: Sep 2025
Posts: 5
Likes: 1
It seems that the issue got a little better but still there's something off around those RPMs. I want to try the exhaust flap fix before i move on to bigger things as it seems like its one of the most common issues with boost problems. I read somewhere here once something about ceramic grease? I looked all over the sticky for that post and i cannot find it. If anyone has seen it, please send me a link to that. Thanks!
Out Of Control!!
Joined: Jun 2004
Posts: 13,799
Likes: 3,228
2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
It seems that the issue got a little better but still there's something off around those RPMs. I want to try the exhaust flap fix before i move on to bigger things as it seems like its one of the most common issues with boost problems. I read somewhere here once something about ceramic grease? I looked all over the sticky for that post and i cannot find it. If anyone has seen it, please send me a link to that. Thanks!
here is are the lubricant links
https://mbworld.org/forums/c450-c43-...bricating.html
And copper grease apparently
https://mbworld.org/forums/c63-c63s-...t-fixable.html
Last edited by PeterUbers; Oct 15, 2025 at 12:24 PM.
