My car has the same issue. The exhaust flap broken, my car had no power. I think that is the problem. After fixing the flap, my car still has no power. Because my car was tuned, dealer blamed the tune cause this issue. But I know it is not the tune. it bothers me very well. If you solve this issue, plz let me know.

 

 

Oh man. Experiencing the same issue for the past month or so. We've done lots of testing, and even brought the car to the Mercedes dealership amg performance center...have yet to figure out the problem we're trying to solve. No codes, no nothing. We did find a tech bulletin called 'power cut above 4,000 rpms', or something along those lines. One cause is the exhaust flap issue....one of mine is stuck. Parts coming from Germany this week. Disappointed to hear that didnt solve the problem. If this doesn't work, will reflash ecu to check the software side. My car has pure stage 1 turbos and tuned of course. Interesting to hear this has also happened to tune only and stock cars as well.

...was going to make a post this week after the exhaust work was completed. Now it seems that exhaust work won't help with this problem. Oof.

I'll report back. If no solution soon, also gonna make a change, even though this is my favorite car on the road. Too expensive of a ride to make only 3-400 hp. Hah. Might have some low miles upgraded turbos available for trade of stock ones soon. Hope thats not the case!!

 

....shouldve noted...car makes boost under 4k rpm, but stops right there, as the tech bulletin states it should.

 

Did you guys smoke check for boost leaks? We did ...found none.

Also, did the dealer replace the actuator motors or mufflers only? Or do they come packaged together?

 

I want to ask you the same thing. Did you replace them both (actuator motors and muffler)? My dealer only replaced the actuator motors. I found that the angle of the flap was not the same as the other side. It works, but cannot completely open and completely closed. I asked them to replace the muffler, but the dealer refused.

I think the problem is on this exhaust. I saw a post about c63s said plug out the actuator motors can make flap 100% open. I tried and the car into the same mode as our issue, no boost after 4000 rpm. When I plug the actuator motors back, everything works fine.

 

We ordered actuator motors only...no mufflers. If the car needs mufflers to work, will def work to have Benz pay for that or just get the AWE setup. This issue has nothing to do with mods apparently.

So your car is working fine now? Under what condition? When you disconnect electrical from the actuators?

 

NONONO, the thing I said was I did it before this issue.

I think only replace the actuators cannot solve the issue, need to replace them both.

 

Ah. I understand now. Well I'll update the thread after we change out the actuators...doesn't look promising at all now, however. Will then move on to the mufflers afterwards I guess.

 

I am planning to do the AWE exhaust upgrade. They are 15% off right now. the price of one side muffler is 1836 USD. But full Awe exhaust is 3200 USD.

 

Oh awesome....thx for that. Had priced it but must've been before sale. 3200 is good price. They said about 3 week lead time if I remember correctly.

 

Maybe we order two, can get more discount

 

So do you guys think it's the butterfly valve getting bound up in the muffler causing it to not open and close properly? If you remove the servo motor, the butterfly valves are part of the muffler?

 

I remember reading somewhere on the forums that the exhaust valve is actually responsible for causing power loss if it fails to open up, I remember AWE was offering a solution to bypass this on the C63s forums. Not 100% sure just going off memory

 

I tested that c63 awe bypass on the e63s (when my car was no issues), it didn't work for e63 and cause lacking power.

 

I agree with you. I guess the butterfly valve got stuck. and the stuck cause the damage of actuators.

 

 

maybe it could be related to this ....

https://mbworld.org/forums/c63-c63s-...-4000-rpm.html

 

Thx for posting this. We actually replaced both lines and the coupled line leading to the boost control valve....same issue. We do have a new boost control valve to install, and will do so when the actuators arrive.

 

Mannnnn. When you say whole exhaust system, do you mean catback and all actuators, which are separate. Thx for the info and clarification.

 

another similar occurence over at C63 forum ... may suggest weak battery ....

https://mbworld.org/forums/c63-c63s-...-anyone-2.html

 

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Thx. My guy reset 'everything' last week, but will have it done again tomorrow for the sake of thoroughness. Will also look at battery independently. Thanks again.

 

Did you pressure the system past 25psi while doing the smoke test?
Just doing a smoke test without pressure will only detect leak at 0 psi.
I have components that hold boost till 15 psi and at higher boost levels the cracks leak.

 

I was there for the vacuum line test @ zero pressure. We replaced the lines and boost control valve...still no boost over 4,000 rpms. I asked if they pressured system...did not pressure past 25 psi, but will be done if these actuators don't solve the problem. Thx for that. We reset everything again yesterday with xentry and had no battery voltage codes.

Update later this morning...