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Greetings, I have been in possession of my 200d CLA for around one year. The vehicle is a 2018 model equipped with a 2.1-liter diesel turbo engine, producing 136 brake horsepower. It also has an automated gearbox with 7 gears. The mileage is 57,000 miles.

The vehicle consistently exhibits a little delay in acceleration, although sporadically.

If I were to complete a week's worth of short trips and then go on a larger excursion. While driving in 7th gear at around 60 miles per hour, when I rapidly press the accelerator pedal, the gearbox downshifts and there is a little delay followed by a gradual increase in acceleration for about 1 second, after which the engine delivers maximum power.

This behaviour occurs only after I have been engaging in various activities for a few days. During the remaining duration, when I accelerate aggressively, the vehicle promptly and effortlessly delivers maximum power as desired.

I am just inquiring if the vehicle is undergoing a diesel particulate filter regeneration process. Additionally, I have noticed a delay in transitioning out of the regeneration mode and achieving maximum power when I rapidly press the accelerator pedal to the floor. During the hesitating phase, a visible emission may be seen from the exhaust when it successfully clears a puff. Uncertain about the tint, but seems to be smoky.

It is peculiar since I have previously owned diesel vehicles that did not experience any delay while exiting a regeneration process.

Or is it something else different? Is there a problem with the vehicle's engine, causing it to move slowly and emit a little amount of smoke, which is just the automobile expelling impurities from its exhaust system.

All feedback is welcomed and valued.

Thank you.

Your gearbox is equipped with adaptive capabilities, allowing it to analyse and assimilate your individual driving patterns, subsequently adjusting its performance to align with your own style. If you have been driving in a calm and controlled manner, the vehicle will respond with a slower, smoother, and more gradual reaction to the accelerator pedal inputs, even when the pedal is pressed firmly. After doing the task several times, the system becomes aware of your intention and its responses get more precise and prompt. Until you resume driving in a calm and controlled manner.

When I accelerate rapidly, the response of the gearbox is not slow. The vehicle accelerates smoothly without any issues, but then has a momentary loss of power and fails to accelerate as expected for around one second. Subsequently, it proceeds in a manner that is predictable and anticipated.

Driving an old school Honda VTEC may be likened to anticipating the activation of VTEC. There is a lack of information or significance initially, but then there is a presence of anything noteworthy.

This serves as the foundation for the often recommended "gearbox reset" or "ECU reset" in online forums. Depressing the accelerator pedal fully while the ignition is in position II is often believed to initiate a reset process, but in reality, it does not.

It deceives the vehicle into believing that you are a car thief evading arrest by Police Interceptors, causing the car to provide its most prompt reactions. However, once it realises that you are only making a quick trip to the Co-op for bread and milk, the car returns to its usual state.

Uncertain whether automobiles as modern as yours possess such a lack of experience, therefore the aforementioned adjustments may or may not momentarily enhance its reactions. An effective approach, however, involves firmly pressing your foot into the accelerator pedal and maintaining this position many times in rapid succession. However, it will not initiate a reset of any kind

It is possible that there is a problem, however it might also be attributed to the vehicle using a mild mapping for the accelerator inputs. The car's behaviour may be modified by software, which uses maps to regulate its functions.

It is necessary to state. Typically, this occurs during the first forceful acceleration of the vehicle. Following this first period of slow responsiveness, it quickly regains its sharpness and precision.

Performing an overtaking may be both bothersome and perhaps hazardous.

The automobile has undergone diagnostic testing using a STAR machine, which has shown no fault codes, save for one indicating that the exterior air quality sensor is not functioning. However, I am sceptical that this issue would have any impact on the engine.

The automobile is equipped with several driving modes.

Eco Sport Individual Comfort

I selected the option "Individual." Enhance the engine and transmission for improved comfort, while optimising the handling to provide a sportier feel.

The sport mode exhibits excessive harshness in gear transitions and excessively high revolutions for urban applications.

It may potentially provide a problem, however it seems to me that the ECUs are just adjusting.

It has been consistently occurring since I acquired it 10,000 kilometres ago. I am curious if anybody else has seen a similar situation and might maybe verify whether it is an inherent "attribute" of the vehicle.

I have seen this phenomenon seldom in many automobiles, although in various models with distinct engine and gearbox systems. My wife perceives it more prominently since she drives with even more finesse than I do.

The vehicle I arrived in was an Audi A3 TDI equipped with S-tronic [DSG], and I must admit that it had a superior transmission. There were no problems with it whatsoever.

I find the Mercedes 7G to be quite rudimentary or unsophisticated in its design and performance, like that of agricultural machinery.

It is mostly a source of annoyance rather than a problem, however.