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Discussion Starter #1
So guys I had some major problems with the gear box and engine for my car and surprisingly mercedes decided to just fix it.

So just bare in mind iv had a C Class as a courtesy car for like a month and the A class for jerky. At low revs it’s 100% fine but if you kick it up a to higher revs when you take you foot off the accelerator at the higher revs the car jerks about a bit, also in my few hours of having the car back this has happened twice where the car is in D but seems to go in N for a seconds where you can put you foot on the accelerator and nothing will happen for a second and the revs will fall like i’m not accelerating at all. But this stuff only seems to happen at high revs, it’s like the car gets confused at higher revs and doesn’t know what to do.

I’m thinking because i’m had the C Class with the 9speed DCT it’s just a better gear box and iv got use to the smoothness of that and I haven’t driven my car in so long. But is the A Class gearbox just weird at higher revs?
 

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Deffo not an experience that I have had; certainly doesn't sound right.
 

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So guys I had some major problems with the gear box and engine for my car and surprisingly mercedes decided to just fix it.

So just bare in mind iv had a C Class as a courtesy car for like a month and the A class for jerky. At low revs it’s 100% fine but if you kick it up a to higher revs when you take you foot off the accelerator at the higher revs the car jerks about a bit, also in my few hours of having the car back this has happened twice where the car is in D but seems to go in N for a seconds where you can put you foot on the accelerator and nothing will happen for a second and the revs will fall like i’m not accelerating at all. But this stuff only seems to happen at high revs, it’s like the car gets confused at higher revs and doesn’t know what to do.

I’m thinking because i’m had the C Class with the 9speed DCT it’s just a better gear box and iv got use to the smoothness of that and I haven’t driven my car in so long. But is the A Class gearbox just weird at higher revs?
Does this mean that MB have now replaced your gearbox and engine, if so that was quick!
 

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Discussion Starter #5
Does this mean that MB have now replaced your gearbox and engine, if so that was quick!
Gearbox was a full replacement and some part of the engine, not the full engine. i’ll find out on Monday as they are going to send me the repair after it’s invoiced to MB.
 

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Discussion Starter #6
That doesn't sound normal. Maybe make a video?
It’s hard for me to make a video, but it happened in the low revs today, I was parked at traffic lights and the car didn’t move till it hit 2.5k revs and just shot off after that. It must be an issue with the gearbox not engaging properly.
 

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That is definitely not normal.

I would suggest that the gearbox needs a software update, and a full adaptation procedure in Xentry.


As you've got nothing to lose - why not try the initial adaptation procedure as detailed in this post?
 

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It’s hard for me to make a video, but it happened in the low revs today, I was parked at traffic lights and the car didn’t move till it hit 2.5k revs and just shot off after that. It must be an issue with the gearbox not engaging properly.
Its your shout obviously but perhaps it is time to talk to the dealer about rejecting the car after all.

You have been more than patient with them, you have had a gearbox replaced that still does not work correctly and the metal partials in the engine oil may have left permanent damage, so in view of the time the car has spent off the road, the disappointment you have experienced that a quality of the car you have been given is not as expected and you no longer have faith that they will be able to resolve the current problems perhaps they could speak to MB about providing you with transport whilst they order a replacement car.

Its worth a try at least but you will need to be firm with them I'm sure.
 

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Discussion Starter #9
That is definitely not normal.

I would suggest that the gearbox needs a software update, and a full adaptation procedure in Xentry.


As you've got nothing to lose - why not try the initial adaptation procedure as detailed in this post?
Just looked at the thread and it seems like it’s a software issue, i’m guessing when they fitted the new bits in they didn’t update them to the latest version
 

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Discussion Starter #11
Try the DIY TCU Reset first, you’ve got nothing to lose!
Just to make sure I have it right

First 1 press the start button to bring power to the car. Then I open the driver door and press the start button twice. Finally I just start the engine.

Just wanted to make sure that’s right, before I give it a go? Just was confused as I seen this and another one where you have to press the accelerator for 5 seconds
 

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Get in car
Close Door
Do not touch the brake pedal at all
Press Start button twice - all lights should come on in instrument panel
Press throttle pedal fully down to floor for at 5 seconds
Press start button again - this should "switch off" the car, but keep throttle pedal pressed for a further 2 seconds
Take foot off throttle pedal
Sit in the car and do nothing, don't open any doors, don't touch the MBUX or start button for at least 2 mins.

Start car as normal, go for a drive.
 

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Discussion Starter #13
Get in car
Close Door
Do not touch the brake pedal at all
Press Start button twice - all lights should come on in instrument panel
Press throttle pedal fully down to floor for at 5 seconds
Press start button again - this should "switch off" the car, but keep throttle pedal pressed for a further 2 seconds
Take foot off throttle pedal
Sit in the car and do nothing, don't open any doors, don't touch the MBUX or start button for at least 2 mins.

Start car as normal, go for a drive.
Thank you i’ll give it a go now
 

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Discussion Starter #15
Get in car
Close Door
Do not touch the brake pedal at all
Press Start button twice - all lights should come on in instrument panel
Press throttle pedal fully down to floor for at 5 seconds
Press start button again - this should "switch off" the car, but keep throttle pedal pressed for a further 2 seconds
Take foot off throttle pedal
Sit in the car and do nothing, don't open any doors, don't touch the MBUX or start button for at least 2 mins.

Start car as normal, go for a drive.
Just tried it now and it hasn’t fixed the issues, I had to rev hard to do an overtake and it reved fine to that point but there was about a 1 second gap of the car not being in a gear while at 6k rev, so I couldn’t accelerate in this time. It’s potentially quite dangerous.

But this ECU reset has made so much difference to gear shifts, you use to feel every shift before and now it’s buttery smooth and seamlessly changes gears when operating normally, so I have to say thank you for that. It’s made the car so much more pleasant to drive. But to fix the main issues I still think a software update is needed.
 

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Good to hear it made some difference.

I would go back to the dealer now, with the complaint of excessive clutch slip, to the point where it’s dangerous pulling out of junctions and overtaking.

In my view, it needs the updated software and an initial adaptation.
 

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Discussion Starter #17
Good to hear it made some difference.

I would go back to the dealer now, with the complaint of excessive clutch slip, to the point where it’s dangerous pulling out of junctions and overtaking.

In my view, it needs the updated software and an initial adaptation.
Thank you very much for you help and thanks for the correct term for my issue. I would have sounded a bit like an idiot trying to explain it 😂😂
 
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