Rick X Joaquim

skratch77

Shut off TC and see if it does it

PJmak

Missfire

hachiroku

blew the welds off the intake manifold. naws

Savage-wp

It's probably the traction control. Turn it off or put it in sport mode.

Savage-wp

And if turning the TC off doesn't fix it, then check your flux capacitor

Rick X Joaquim

LoFox

If it's not the TC then it sounds like the ECU cutting fuel and/or pulling timing to protect the motor; it could be related to high knock or misfire. (If you have an ODB2 scan tool, there is a good chance you have a pending code you can retrieve which might shed more light as to what happened.)

Rick X Joaquim

LoFox

It can take a few occurrences of a problem before the ECU will flag it, usually 1-2 occurrences is not enough (although from your description it sounds like you've encountered this issue at least a handful of time so I'd expect there to be a pending code at minimum.) I still feel that it should be at least one of the issues I mentioned, that is either high knock or misfire ... Short of reproducing the issue a few more time to allow the ECU to actually throw a code I'm not sure how you could proceed next or taking it to a shop and showing the mechanic first hand.

Has anything with the car changed recently which might correlate with the behavior of the motor, such as ECU flash, were the air filters cleaned or replaced, or was there any condition where they might have become significantly more dirty at a faster rate (really depends on your location, but maybe sand from a beach or desert or carbon if your area was recently hit by a fire ... I know sounds kinda strange, that probably not applicable to most people, I live in CA and if one of our fires happens to be near where I live my air filters are completely black afterwards.)

Rick X Joaquim

skratch77

I'm betting it's the air flow meters.

LoFox

The MAFs? It could be, they're pretty easy to get to so it couldn't hurt to clean them yourself and it very quick (watch a quick youtube video on how-to.)

LoFox

Sound unlikely to be the tune in this case, and I agree with you in most of my experience it's never the tune.

Rick X Joaquim

LoFox

Personally, I've never encountered an ECU that's been corrupted due to a flash but I have seen the 'excuse' thrown around, I feel like on the level of likelihood a corrupt ECU would fall below 'bad tune.'

(The AMG ECUs are a bit of a black box, I also have an Evo which has a lot more open software available for self tuning and hot discussions about topics so that's where these types of issues tend to come up, ie "I flashed a tune now then X happened." In almost call cases I recall its never been the ECU or tune.)

I think it can be pretty hard to test out a new ECU without getting Mercedes involved simply because of the lack of tech that we have available; any ECU that you get will be coded to the car that it came from so you can't just swap them in and out. At minimum the car will have an immobilizer which will prevent it from starting (and with it being Mercedes I'm sure there are probably other 'safeties' in place to prevent doing this.) On the Evo for instance one can very easily pick up a used ECU on ebay, either disable to immobilizer or re-code it to match their immobilizers code and you're good to go.

In the case that the ECU was damaged, I would expect the standard behavior for it to be that it just doesn't work at all, car doesn't turn on. In your case it would be very selective, as everything seems to be fine 99% of the time except for WOT and high engine load, from a damaged hardware perspective this seems hard to explain.

If you're set on testing the ECU (I feel it could be useful just hard to accomplish quickly and inexpensively) I think you might have two options:
1. Take it to Mercedes and have them flash it with a factory image
* they probably won't want to do this right off the bat, they'll want to diagnose the issue and probably as a last resort flash the ECU (you should also probably tell them that you had it flashes because I know they have the ability to only overwrite parts of the ECU, its not an all or nothing process) So you might want to to do a full flash to whatever degree that is possible.
2. Talk to a tuning shop like Kleemann, they have bench hardware that they use to verify their tunes on ECUs that customers send it. You might be able to send in your ECU and see if they're able to use their test hardware to validate it.

Rick X Joaquim

LoFox

Any new developments with the WOT issue? Did you end up getting a new ECU?

Rick X Joaquim

the_indian_kid

I am experiencing this same issue; or similar. I recently got my m156 engine rebuilt, and suoercharged. No issues when i was NA. But now with a blower, when i go WOT, car hits a brick wall at around 6000 rpms and followed by fuel cut after. However if i perform like, 80% throttle, or less, it goes to redline..i tried different tunes, different injectors, no joy.

Has this issue been solved for you? If soo, what was the issue? Thank you.

Joshinator99

Did your tuner have you send him data logs of when this is going on…? Should be pretty easy for him to see what’s up.

the_indian_kid

Yeap, everyone took a peek at it. I had shops from instagram dial into my xentry via team viewer, did live runs. No joy. 😔 ny suspicion is the tcu/ valvebody, maybe the trans oil, or ecu needing tune in person. I even went the Syvecs route. Same damn issue. So clearly the ECU is okay.

SROC276

Just a quick check….but have you tried changing the actual pedal? Experienced this a few times a while back and it turned out to be pedal and incorrect readings. Worth a try. If not…hope you still get it resolved. Sometimes it’s the dumbest of things.

BalanBro

I was just about to type the same thing. My car did this intermittently, but with no codes or anything displayed. About a year later I actually got a code for the accelerator position, and it occasionally went into limp mode when the pedal was pressed all the way to kick-down. I since replaced the pedal with a new one from FCP Euro, and never had either problem again.

My theory is that a faulty accelerator position signal might be screwing up the torque management within the ECU, but it won't throw a code until it gets bad enough.

SROC276

Thumbs up! We’ll hope OP gets this sorted. Yes my car would throw an ABS fault code on occasion and then nothing for a few other instances. Changed the pedal and it stopped. Seems like these pedals may have an issue after 70-80k miles.