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Discussion Starter · #1 · (Edited)
Hi all
I come across with a strange problem with my 45s recently.
I drive my 45s everyday. In recent months when i play with it in S+ or R mode for 20 minutes it suddenly enters in limp mode, losing power like the turbo is gone. I stop the car, let it rests for a few minutes and everything is back to normal, then the problem repeats!

The car went back to the dealer and nothing was found, but the problem is still there, only it comes earlier and earlier! I send the car back to the dealer again and again and still problem not solved!

I am wondering if it has anything to do with the early hot summer here in asia ...

Any one encounter this problem ?
Thanks.
 

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Discussion Starter · #3 · (Edited)
Have you done any upgrades?
Only the 'software', l think it's more likely a firmware update everytime the car goes back to the dealer.... Other than that the car is exactly the same as the first day it touches the ground.
 

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Have a look at this thread. I will move yours to it.
 

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Discussion Starter · #5 · (Edited)
Have a look at this thread. I will move yours to it.
I read this thread as well, l experienced similar problem before with my previous 45.

But this time the problem is totally different.
It's something else, feels like the turbo is gone after a few minutes of high RPM R mode driving, and going back to normal after I let the car rest for a while, but the problem keeps repeating. No warning signals are shown during the limp mode.

So can you do the other way round, separate my thread with this one, please?
 

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What's the oil temp at when the car starts to loose power?
 

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I read this thread as well, l experienced similar problem before with my previous 45.

But this time the problem is totally different.
It's something else, feels like the turbo is gone after a few minutes of high RPM R mode driving, and going back to normal after I the car rest for a while, but the problem keeps repeating. No warning signals are shown during the lame mode.

So can you do the other way round, separate my thread with this one, please?

I've demerged the threads as we await the outcome.
 

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Can I ask. With all these updates. Has your car had the speed limiter set to the 110 kph you're showing.
 

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Could you check the transmission temp when this happens? Is it about 85°C or higher?
Also, what you're calling power loss, does it feel constant, or is it like fuel cuts/hiccups? And if it is, does it happen shortly after gear change?
 

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I previously had a underboost hidden error code but the check light never came on until I scanned it with my OBD reader.

And before I cleared it, the car was in limp mode and you can immediately experience the power loss.
 

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Discussion Starter · #13 ·
Could you check the transmission temp when this happens? Is it about 85°C or higher?
Also, what you're calling power loss, does it feel constant, or is it like fuel cuts/hiccups? And if it is, does it happen shortly after gear change?
I didn't pay attention to the transmission temp.... You think it's overheating and caused the problem?

The losing power is quite like the car becoming another one, say an A200, or worse.
 

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View attachment 8144

Everything seems normal.... except the car doesn't want to go fast!
That's the coolant temp displayed. I recall reading that the car cut power when oil temps go beyond 120 degrees. You can monitor both oil and gearbox temps and see if there is a pattern when the power starts to cut out.
 

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Discussion Starter · #15 ·
That's the coolant temp displayed. I recall reading that the car cut power when oil temps go beyond 120 degrees. You can monitor both oil and gearbox temps and see if there is a pattern when the power starts to cut out.
Thanks for the advice! Will check it out, right now the car is back to the dealer....
 

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Discussion Starter · #16 ·
That's the coolant temp displayed. I recall reading that the car cut power when oil temps go beyond 120 degrees. You can monitor both oil and gearbox temps and see if there is a pattern when the power starts to cut out.
So is there any warning signal on dashboard for oil and gear box temps??
 

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So is there any warning signal on dashboard for oil and gear box temps??
Go to the central display and select AMG Performance,from there select engine and that will give you engine oil and gearbox oil temps,along with power and torque.
This is what ut will look like -
8169
 

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Discussion Starter · #18 · (Edited)
Go to the central display and select AMG Performance,from there select engine and that will give you engine oil and gearbox oil temps,along with power and torque.
This is what ut will look like -
View attachment 8169
8184


No power again after 15min drive today.
Gas pedal was all the way down when i took this shot, all temperatures seemed normal, the BOOST bar showed nothing......
So sad and angry!
 

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Temps are way too high for a 15min drive. Gearbox temp even more so, considering it doesn't heat up nearly as fast as the engine. For gearbox 85°C is of the highest I've seen and that's after several runs at 25-28°C ambient. For the engine I've seen 105°C again after several runs (spirited driving would be an understatement), but it only takes a few minutes of normal driving to drop back down to about 92°C. Our oil cooling system (cooler and whatever else is involved) is impressive, it's one of the things I'm mostly impressed with. If yours is failing, might explain why it's going into limp mode. How long does it take for the engine to cool back down to let's say 90°C?
 

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Hi,

Took delivery of my A45S (Designo Mountain Grey Magno A45 S AMG ) from Mercedes-Benz of Edinburgh East mid April 2021. Lovely car but only managed to put 1500 miles on the clock so far and mainly short journeys in Comfort. Early on I got a couple of "Transmission Errors". Nothing since but there is definately something odd going on with the transmission which means at times there seems to be no power or something doing a CTL-ALT-DEL!

Craig
 
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