[zltm089]

wow! interesting thread!....

I have changed my brake discs and pads, all round and when first installed, the computer showed 24000 miles left on them....front and rear......

NOW

its showing 19000 Front and 15000 Rear!!! why is the rear pads wearing off quicker? is it because of the DSC? ...in thats the case, then I'll start to switch it off all the time now!

[NFS]

Originally Posted by zltm089

its showing 19000 Front and 15000 Rear!!! why is the rear pads wearing off quicker? is it because of the DSC? ...in thats the case, then I'll start to switch it off all the time now!

Definitely the DSC. But switching it off just means the tyres wear instead

[zltm089]

Originally Posted by NFS

Definitely the DSC. But switching it off just means the tyres wear instead

ahhhhhhhh damn it....if only i knew this!!!!....I though that the DSC would only cut the power and didn't actually "brake".....going to switch it off from now on!...

[marcel b]

it is simple. Our cars do not have a limited slip diff. This means the inner backwheel starts spinning quite fast. With DSC on, the brake of the inner wheel will be applied to limited the wheel spin. Power cut is only when you push it quite a bit harder.

[HighlandPete]

Originally Posted by zltm089

wow! interesting thread!....

I have changed my brake discs and pads, all round and when first installed, the computer showed 24000 miles left on them....front and rear......

NOW

its showing 19000 Front and 15000 Rear!!! why is the rear pads wearing off quicker? is it because of the DSC? ...in thats the case, then I'll start to switch it off all the time now!

Driving normally won't be braking the rear wheels, but the harder you drive the more the brakes will be working. Don't forget the DSC is more than helping control traction, so could be an expensive mistake to have it switched off. Imagine you are on the limits and find you can't get out of trouble, you have switched off DSC, it can't help you keep out of the hedge, ditch, or worse.

Like ABS, DSC is a safety system.

HighlandPete

[MERLIN335i]

Originally Posted by marcel b

based on this... there is for sure something wrong with your car. If a mechanic would drive it, he would for sure feel it. I once had a strange feeling in my former Z4M, brought it to the garage several times for it. Chief mechanic went for a drive with me so I could show him what I felt. They can plug a laptop in while driving to be able to see what DSC is doing. If you just bought a car there, they at least can have a mechanic have a drive with you! If not, isn't there a possibility to escalate this to BMW UK?
Sorry to hear all of this, this is for sure not what you had in mind buying a BMW. But believe me, as soon as this is fix, you will love it. Don't give up on her!

Marcel,

The car has been driven by the dealer "Master Technician" on numerous occasions and always says "seems alright to me" I have also had both the Dealer Principal & BMW UK Area Technical Manager in the car with me on journeys, but you cannot really demonstrate "lack of throttle response". I have asked for them to drive the car with the "GT1" machine connected to monitor the car, the only comment I get is that it would take two technicians to do this. This would require a technician who can instantly
recognise what the machine is telling him (reading between the lines, I am not sure they have someone of this calibre, they only seem to be able to react when being told what is wrong by a fault code, cannot work it out for themselves).

[MERLIN335i]

Originally Posted by HighlandPete

What sort of road surfaces are you driving on? A lot of smooth hardtop? You mention low average speeds, but what sort of driving are you doing, stop start, lots of roundabouts? You also say the car is totally different with DSC totally switched off, again what sort of driving? From light to moderate, in comparison to light to moderate with DSC on.

I can't get my head around the throttle response bit and DSC being linked, if you drive lightly. DSC shouldn't even be getting a look in, in normal driving. Something is not adding up here.

HighlandPete

Pete,

This is exactly my point at the average speed recorded, DSC shouldn't even be getting a look in, That is why I am sure there is a fault with the DCS/DTC system, it works far too early. Because of the lack of enjoyment driving this car, I tend not to go far in it now. In the early days it went on 200 mile trips, all types of surface, still had the problem.

The performance/throttle response between DSC on and everything switched off is night and day.

[MERLIN335i]

Originally Posted by NFS

If it IS a problem with the DSC, then it should have been obvious to the road testing mechanic.

The car has been driven by the dealer "Master Technician" on numerous occasions and always says "seems alright to me" I have also had both the Dealer Principal & BMW UK Area Technical Manager in the car with me on journeys, but you cannot really demonstrate "lack of throttle response".

[NFS]

Originally Posted by MERLIN335i

This is exactly my point at the average speed recorded, DSC shouldn't even be getting a look in, That is why I am sure there is a fault with the DCS/DTC system, it works far too early. Because of the lack of enjoyment driving this car, I tend not to go far in it now. In the early days it went on 200 mile trips, all types of surface, still had the problem.

The performance/throttle response between DSC on and everything switched off is night and day.

I'm not sure that the average speed tells you much. Mine is quite low at the moment, because I've done a fair bit of local driving over the Christmas / snowy period.

That doesn't mean that the DSC has not been active though. It will cut in at relatively low speeds if you are cornering fast enough to brake traction (which on wet greasy icy surfaces could be very low indeed).

If anything the DSC light comes on far less on my 335i than it did on my 330i. The system seems to allow far more wheelspin, which is a good thing. The flashing light also comes on less, although I can feel the system working.

Switching DSC off does sharpen throttle response on all cars. I would say by around 25%. Is it a greater difference on your car?

I also paid attention to the first 25% of throttle travel on my car driving home last night. On my car there is a fair amount of travel at the beginning of the throttle movement, so the first 20% does very little anyway. Beyond that point there is a variance in response as the car begins to accelerate, which seems to depend on the turbos.

It's not lag, but it's the only point where you can tell that there is 'something else' contributing to the power. To me it feels like a much reduced version of the 'torque convertor locking up' sensation you get with an auto.

I'd say that the difference in response is only 25% or so and only for a VERY short period of time (an instant really).

What was different about the other 335i you drove?

[MERLIN335i]

Originally Posted by NFS

I'm not sure that the average speed tells you much. Mine is quite low at the moment, because I've done a fair bit of local driving over the Christmas / snowy period.

That doesn't mean that the DSC has not been active though. It will cut in at relatively low speeds if you are cornering fast enough to brake traction (which on wet greasy icy surfaces could be very low indeed).

If anything the DSC light comes on far less on my 335i than it did on my 330i. The system seems to allow far more wheelspin, which is a good thing. The flashing light also comes on less, although I can feel the system working.

Switching DSC off does sharpen throttle response on all cars. I would say by around 25%. Is it a greater difference on your car?

I also paid attention to the first 25% of throttle travel on my car driving home last night. On my car there is a fair amount of travel at the beginning of the throttle movement, so the first 20% does very little anyway. Beyond that point there is a variance in response as the car begins to accelerate, which seems to depend on the turbos.

It's not lag, but it's the only point where you can tell that there is 'something else' contributing to the power. To me it feels like a much reduced version of the 'torque convertor locking up' sensation you get with an auto.

I'd say that the difference in response is only 25% or so and only for a VERY short period of time (an instant really).

What was different about the other 335i you drove?

Thanks for your comments.

This problem has existed from day one, the same whether on dry or wet roads.

The difference in power/response between DSC on or off, is night & day.

Pedal travel seems linear, first 20% just the same as the rest.

The other 335i supplied by BMW UK was running the anti waste gate rattle/bad lag
V29.2.0 software, also had been stood for eight months, so a waste of time really.

I have very latest spec turbos and actuators, with V34.0 software.

The more I used it with DSC turned off the better it got (up to a point), obviously the adaption values have now been set, using "turned off" data.

I think the excessive pad wear and brake dust on rear wheels (rather than the front) point to a fault with the DSC system (rear wheel speed sensor faulty ??) it is far far too sensitive.

Maybe the answer is a LSD, and continue to run with system off.

I feel I should say (we know this site is monitored) that I have no doubt of my Dealer Principle's desire to solve the problem, but I strongly question the Service Department's ability to solve it !!!!!

[MERLIN335i]

I find it strange that Tony has not commented on this problem, he is usually fast out of the blocks to help with other 335i problems. I don't see how, but maybe I have upset him ??

[willhollin]

Originally Posted by MERLIN335i

I find it strange that Tony has not commented on this problem, he is usually fast out of the blocks to help with other 335i problems. I don't see how, but maybe I have upset him ??

He's a busy man.

Have you considered using another dealer?

[MERLIN335i]

Originally Posted by willhollin

He's a busy man.

Have you considered using another dealer?

If I take it to another dealer (Battersea or whoever) and as usual it shows no fault codes, the dealer will not be paid by BMW, therefore the dealer will not absorb the cost
as I did not buy the car from them, as he has made no money from me, and I will be charged for the time @ £120+ per hour.

I do not see why I should pay, the car is under warranty that has only done 5000 miles
and the fault has existed from very early on.

[HankE92]

Originally Posted by MERLIN335i

The difference in power/response between DSC on or off, is night & day.

If the above statement is true then it would be easy to demonstrate during a test drive with a BMW mechanic in the car.

[MERLIN335i]

Originally Posted by zltm089

ahhhhhhhh damn it....if only i knew this!!!!....I though that the DSC would only cut the power and didn't actually "brake".....going to switch it off from now on!...

zltm089

Have you tried it with DSC/DTC completely off ???

What did you think, is it slightly better or much better as mine is ???

[NFS]

Originally Posted by MERLIN335i

The difference in power/response between DSC on or off, is night & day.

Night and Day isn't very descriptive really. It can mean different things to different people.

With DSC off is the throttle response 25% / 50% / 75% / 100%?

If it's more than 25% then I would say that DSC is DEFINITELY your problem.

The next question is if your DSC is actually broken or if you just don't like it. The only way to understand that is to drive it back to back with another car.

I've asked a couple of times about the 335i you drove. Just saying it was a waste of time is again not very descriptive.

Did you perceive any similarity with your car in terms if throttle response / DSC intervention? Was it totally different? Was the difference between DSC on and off as pronounced?

[zltm089]

Originally Posted by MERLIN335i

zltm089

Have you tried it with DSC/DTC completely off ???

What did you think, is it slightly better or much better as mine is ???

hmmm...ok since reading this thread and learning that that bloody DTC/ DSC is "using up" my brake pads, I've started to drive with DTC off ....(I can't be bothered to hold the button every morning...so I guess that makes the DSC still on...)


Throttle response for me is the same.....but then again, its town driving with traffic....


I will switch off the DSC/ DTC completely and start testing throttle response from now on! and you can get me a beer at the next UK meet!!!....

But, so far every time I've switched off the DTC the car "feels" faster when accelerating from standstill (maybe its just in my mind...i may be wrong...)

but i'll pay more attention now and will let you know....

theres so many factors to consider though when testing these kind of stuff....(gear selected DS , D or M , road surface, hill gradient etc....I found that a slight uphill, really triggers my orange light!!!! )

[zltm089]

Originally Posted by willhollin

He's a busy man.

Have you considered using another dealer?

are you his PA? lol

[G33]

ive not notced the throttle response tbh. will look out for this next time tho

however do realise how much work the DSC does its job tho as on the idrive the front pads apparently have 45,000 miles left in them when the rear have 14,000

[E92Fan]

Originally Posted by MERLIN335i

I find it strange that Tony has not commented on this problem, he is usually fast out of the blocks to help with other 335i problems. I don't see how, but maybe I have upset him ??

1 Busy
2 Entertaining 'dancing friends'
3 More busy


Perceived DSC issues are very common during winter months, because the differences between DSC activation and non-activation are so much more pronounced. As has already been said, the DSC system is almost constantly working to control the back wheels and to prevent loss of traction, in either the linear axis (as in direction of travel) or in the transverse axis (side to side motion). The DSC's first option is to selectively brake one or more wheels in order to minimise wheelspin. If this is not sufficient, the DSC system will then progressively shut down the throttle to reduce power until suitable grip levels have been regained.

In the current weather conditions, the DSC system will always work more than during warm summer months, and because of this greater intervention the difference between throttle response with DSC on and off is much greater, and hence more noticeable to the driver.

There is another element that shouldn't be overlooked - throttle adaptations of the car. The car learns how the driver uses the throttle, and if it senses that the driver demands a more aggressive throttle application under normal driving conditions, the ECU will adapt accordingly and deliver more go with less pedal travel. This therefore means that power delivery is more sudden, and this can have an effect on DSC activation, especially when the weather is how it is now.

It could be that your car is electronically aggressive with throttle application, and the DSC is having to intervene in a more active fashion, hence why you feel that there is a poor response. Ask your dealer if they would reset the ECU adaptations - it's an easy process and might alleviate some of the issues you are experiencing.

[MERLIN335i]

Originally Posted by NFS

Night and Day isn't very descriptive really. It can mean different things to different people.

With DSC off is the throttle response 25% / 50% / 75% / 100%?

If it's more than 25% then I would say that DSC is DEFINITELY your problem.

The next question is if your DSC is actually broken or if you just don't like it. The only way to understand that is to drive it back to back with another car.

I've asked a couple of times about the 335i you drove. Just saying it was a waste of time is again not very descriptive.

Did you perceive any similarity with your car in terms if throttle response / DSC intervention? Was it totally different? Was the difference between DSC on and off as pronounced?

I really appreciate the time you are spending on this.

Throttle response is around 50% better with DSC off.

With the back to back car, because it had bad lag problems (software) it was hard to know whether it was that causing the bad throttle response or the bad response was down to DSC intervention.

Turning the DSC on/off made very little difference, but lag may have influenced this.

To do a true back to back, the cars need to be identical, the car provided was the only manual in BMW UK stock at the time, but with the different turbos and software, it was never going to be a true comparison.

The continual varying throttle response really messes with my head, I need to know what I will get when I press it.

[MERLIN335i]

Originally Posted by zltm089

hmmm...ok since reading this thread and learning that that bloody DTC/ DSC is "using up" my brake pads, I've started to drive with DTC off ....(I can't be bothered to hold the button every morning...so I guess that makes the DSC still on...)


Throttle response for me is the same.....but then again, its town driving with traffic....


I will switch off the DSC/ DTC completely and start testing throttle response from now on! and you can get me a beer at the next UK meet!!!....

But, so far every time I've switched off the DTC the car "feels" faster when accelerating from standstill (maybe its just in my mind...i may be wrong...)

but i'll pay more attention now and will let you know....

theres so many factors to consider though when testing these kind of stuff....(gear selected DS , D or M , road surface, hill gradient etc....I found that a slight uphill, really triggers my orange light!!!! )

Many thanks for the reply.

Sorry didn't realise your's was and auto, so no doubt it will be different.

Buying Beer, driving home, TUT TUT !!!