Acceleration Delay

[Howard Burns]

Hi Everyone,

I have an annoyance with my new C220 auto. From standstill, and particularly waiting at a roundabout, when I accelerate, there is a delay before any meaningful power is applied to the engine. It is only a second or two but when I am trying to proceed around a roundabout that delay could be dangerous. I don't expect instant 60mph, but this delay seems unacceptable. Anyone else experienced this?

 

[Naraic]

What gear are you starting in?

 

[Howard Burns]

It's an auto - so 1st gear.

 

[V6Matty]

do you drive in S or C mode by any chance?

 

[Naraic]

It's an auto - so 1st gear.

It's an auto MB so could be 1st or 2nd...back to you. Since you didn't know this...it is probably 2nd.

 

[Howard Burns]

I have experienced this delay in Economy, Comfort and Sports, although in Sports the acceleration is much quicker but nevertheless after a delay.

When the car is on and waiting the drive shows as D1,

 

[V6Matty]

hmm, sorry maybe I'm wrong but is this a 203, 204 or 205 we are talking about, I'm guessing 204 in which case you do need to still be driving with it in S, driving in C will (and I could be wrong) start you off in 2nd gear and change up earlier.

 

[Howard Burns]

Not sure what you mean by 203, 204, 205. The car is is a C220 auto sports Bluetech.

 

[V6Matty]

ok these are the model designations for the C class. Looking at some of your other posts I see its a 2015 model which would make it a new W205 (if you have a look at your VIN number it will start W205xxxxxx).

in which case I'm not sure how the new box works as they are a little new for many of us here, but I do suspect if you check the manual it will say the S mode is the normal one for use over C or E

 

[Howard Burns]

Hi Matt,

Thanks for your explanation. Yes it is a 2015 C220. I understand what you mean by driving in Sports, but doesn't that rather defeat the whole idea of economy. It would seem strange to have to use more fuel (in sports mode) in order to overcome a potentially dangerous issue at a roundabout.
I thought MB was at the forefront of engineering technology, which is why I purchased the car, but it would appear that in this particular design aspect of engine management they have overlooked what I consider to be a safety issue.

Your thoughts???

 

[Oarsman]

Just because you set it for sports mode you do not have to drive in a sporting manner.
Just drive normally.
You may actually use less fuel as the engine will not need to rev so high to pull away, as it does in C mode.

 

[V6Matty]

checking the owners manual it states:

Drive program S (Sport)
Drive program S is characterised by the following:
• the vehicle exhibits sporty driving characteristics.
• the vehicle pulling away in first gear.
• the automatic transmission shifting up later.
• as a result of the later automatic transmission shift points, the fuel consumption possibly being higher.
• the suspension exhibits stiff springing and damping settings (vehicles with AIRMATIC).
Drive program C (Comfort)
Drive program C is characterised by the following:
• the vehicle delivers comfortable, economical driving characteristics.
• the vehicle pulling away more gently in forward and reverse gears unless the accelerator pedal is depressed fully.
• increased sensitivity. This improves driving stability on slippery road surfaces, for example.
• optimal fuel consumption resulting from the automatic transmission shifting up sooner. The vehicle is driven in the
low engine speed range and the wheels are less likely to spin.
Drive program E (Economy)
Drive program E is characterised by the following:
• the vehicle exhibits comfortable, economical driving characteristics.
• the vehicle pulling away more gently in forward and reverse gears unless the accelerator pedal is depressed fully.
• increased sensitivity. This improves driving stability on slippery road surfaces, for example.
• optimal fuel consumption resulting from the automatic transmission shifting up sooner. The vehicle is driven in the
low engine speed range and the wheels are less likely to spin.
• during deceleration, the engine is disconnected from the drive train. The vehicle uses kinetic energy and consumes
less fuel (overrun mode).
• the performance of the air-conditioning and heating systems is reduced.

so essentially you can run in Comfort mode but if you need to accelerate quickly you have to use full throttle (this has been the same since the late 90's I believe), I'd say its just something you have to get used to or maybe run in Sports as many of us do.

 

[Howard Burns]

Thanks everyone for your good advice. I suppose, as you say, I need to get used to this way of driving. Still, after 50 years of driving there is always something to learn.

Thanks again.

 

[V6Matty]

My bother has ordered a C220 estate AMG, I have warned him he will have to learn how to adapt his driving style for pretty much this exact reason, I did let him have a drive in my 211 so he had an idea but he ended up just flooring it everywhere, guess I can't blame him the old girl does move very well

 

[mancman]

Mine is exactly the same, a guy at work has a Peugeot and his does this and if your behind him you can tell when this happens because all of a sudden the car takes off, when coming to roundabouts I now use the controls on the steering wheel to change gear it's much more responsive than waiting for the box to do it.

 

[Howard Burns]

Hi, That's interesting using the manual gears. Do I take it that there is no delay when accelerating in manual 1st gear at a roundabout?

 

[V6Matty]

at my guess, using manual gears will be like setting things to sport although once you finish manually changing gears it will go back to eco/comfort without the need to select it.

 

[Howard Burns]

Brilliant - I'll give it a try - once it's stopped raining!!!

 

[mpwnbr]

I'm not the most technical minded when it comes to cars, but is this not just a case of Turbo Lag? I've experienced it in previous BMW's, and although alien at first, I did get to a point where I'd put my foot down, and at least I knew the acceleration was about to happen.

 

[V6Matty]

nope afraid not, it is very noticeable when selecting C the difference in how the car takes off compared to S, essentially its starting in 2nd gear hence it feeling like there is no power, it stumped me the first time I selected C by mistake