BMW Forums : BimmerForums banner

1 - 20 of 84 Posts

·
Registered
Joined
·
16 Posts
Discussion Starter #1
Hi all, I'm new to this forum and would be greatful for any advice.

I have just sold my old car which was a 2008 320D MSport in Le Mans blue. My favourite car and never had an issue with it in all its time. The reason for mentioning my old car is show I'm used to the sound that the 2 litre engine made within the cockpit.

I bought a new car which is a 520D M Sport with M Sport Plus pack. Car is lovely and about 1 month old. One thing that I am noticing and I cannot reproduce this on demand and I cannot find conditions that this occurs in. However in certain conditions "unknown to me" at around 1500revs the car will make almost like a vibrating rumbling sound through the :banned: pit. Quite unpleasant on the ears. . It can last for about half an hour at a time Is most annoying. Inside it sounds very boy racer deep exhaust rumbling through that cockpit.I have taken to dealership an wasn't able to reproduce. They did say there had been some people with similar faults in the old chassis and BMW had advised exhaust tension and a fix.

Supposedly when my car was in for the day they realigned the exhaust. This has made no difference. I'm struggling to think what I can do next. I can't keep taking my car in with a fault that I can't reproduce.

Any advice would be much appreciated.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #5
Ive raised this in another BMW forum and have got the same response. One person thought timing chain issue, but pointed out mine is a B47 engine not the N47. Then people started saying it was DPF Regen

Can someone explain what this is this DPF Regen is, how often it occurs, what conditions make it occur, does this happen on the fly etc

Many thanks
 

·
Registered
Joined
·
2,759 Posts
The Diesel Particulate Filter is a device in the exhaust which traps some of the soot left over from the combustion process. Periodically the system aims to burn the soot out of the filter to clean it and prevent it from becoming blocked. It does this by modifying the exhaust mixture to raise the temperature of the elements in the filter. This is the regen(eration) process.

Frequency of the regen is determined by driving habits. Diesels are more suited to motorway cruising which allows more for a steady state exhaust. Lots of start/stop acceleration as with urban driving produces more soot and so the filter tends to clog up more quickly.

Its possible in your case that the gas flow modification is generating the noise by triggering some form of resonance. You mentioned a previous issue with exhaust fitment.
Worst case the solution would be a new exhaust system. There is probably a cheaper and less drastic fix although it may still entail removal and refitting of your existing pipe.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #7
Right, the car has been into Sytner this morning and they think they have found the issue even though I was unable to demonstrate again on the day. They think, its to do with the DPF and how it is attached to the exhaust. Nothing to do with the actual component itself failing. The guy seems to think there is any issue on the assembly and how its been attached which means there is some movement on the unit!. They have ordered a new DPF which is on back order and due to be fitted on the 9th March. Supposedly even though the way the DPF is connected allowing some movement, this is not something that can be resolved without a whole brand new one? I'm confused? Supposedly they have had another car with same issue and this fixed it

I will update you all soon. FINGERS CROSSED!
 

·
Registered
Joined
·
267 Posts
My guess is the Dealership has checked back with BMW in Germany, especially if it's a new car, and they've advised the corrective actions that's planned for your vehicle. It's likely that they have seen this issue from other dealers, just hope your not leading the pack on this one!
 

·
Registered
Joined
·
16 Posts
Discussion Starter #9
Sooooo, just picked up car from Sytner.

They ended having to keep the car for an extra day as id mentioned whilst there about the brakes squealing too. Supposedly this also is another common issue with the brake compound used on the brake pads on models within 2014. These were also replaced completely as well. Bonus! It would have been nicer if I'd have done more than 3k on the car to benefit from some new pads in terms of saving money later down the line!

Anyway, "the noise".

So far so good! Granted it is a bit early to tell but even the car itself sounds quieter and smoother under normal driving that previously. Ill come back in 1wk to give a final conclusion as the sound was getting worse and almost happening every 1 of 2 drives. This is supposedly becoming more common and Sytner have advised i'm the 3rd person at that particular garage that they have fitted a new DPF and fixings

Thanks for all your input, update you further soon
 

·
Registered
Joined
·
16 Posts
Discussion Starter #10
Right, did some heavy driving around the weekend and sound is back :( . Managed to capture some recordings this morning and heading over to Synter this afternoon. Keep you posted. Sorry if I jumped the gun. It initially felt so much better.....

I've had uploaded the sound my car makes for people to listen. I have included a clip with the car without the sound. This is normal driving with some high revs and no sound what so ever. The other audio shows the car with the sound. http://1drv.ms/1xxl7Z9 . The sound can be picked up if you listen closely and have your speakers on quite high. Half way through the one clip with the sound. I open the window so you can hear the sound from outside. Sytner haven't fobbed me off yet saying they are unwilling to help due to intermittent fault. If they do try that ill be calling BMW UK as this is unacceptable for a car of this value. Its also costing me time, effort and sanity.
 

·
Registered
Joined
·
85 Posts
The exhaust clamp can crack that holds the dpf section to the centre section which can cause blowing and in some cases cause the exhaust to hit which will cause rattles and knocks.
 

·
Registered
Joined
·
285 Posts
Sounds like my car when its carrying out a regen? the exhaust sounds boomy and noisier than normal but its carrying out a regen, it happens from time to time? to me its part and parcel of DPF's
 

·
Registered
Joined
·
14 Posts
I think I also have this issue with same car 520d, one month old.

I am not sure this is due to a regeneration as many times it happens from a cold start. When it happens is easy to see exhaust vibrating more than often.

Have you guys had any feedback from BMW?
 

·
Registered
Joined
·
14 Posts
I think I also have this issue with same car 520d, one month old.

I am not sure this is due to a regeneration as many times it happens from a cold start. When it happens is easy to see exhaust vibrating more than often.

Have you guys had any feedback from BMW?
Anyone with similar issue?
 

·
Registered
Joined
·
24 Posts
I've got exactly the same issue on my 2015 520d, sounds like exhaust blowing on nearly every trip, can't get it to do it when at the dealers which is driving me mad so taken back to Preston main dealer who are looking at this and I'll let you all know the result. Interesting thing is the loan 520d I've been given is doing exactly the same thing but not as often.
 

·
Registered
Joined
·
24 Posts
Ok, collected my car today and as I expected fobbed off that it's normal for the car to make this noise and told if I want to pursue I would have to contact BMW directly...I've obviously pointed out that I think they should do this as I bought the car from them only 3 months ago and after seeing the service manager he agreed they would now do this.
So at present I'm no further on but if I can find out any info which might help others I'll let you all know.
 

·
Registered
Joined
·
2 Posts
I had almost the exact same problem since the car was about a month old, it's now just over a year. Went to three different dealers and was told either they couldn't find the noise or it was normal. I specifically asked on several occasions if it was related to the EGR or DPF (as someone I know in Germany who works for another manufacturer suggested it may be)

Then, a month and a half ago (and 1 year and 22,000 miles) the car started loosing coolant at an extraordinary rate, and was recovered to the dealer who eventually diagnosed a fault with the EGR Cooler and it was off the road for well over a month due to an 'international supply issue' with the part (reading between the lines I think (and hope, lest it fails again) that this means the part was redesigned and they were aware of the problem) - they accidentally let slip there was three cars in my local dealer alone waiting for the same part.

Having finally got the car back, so far it's not making any odd exhaust noises and drives as smoothly as it should. We've also noticed a marked improvement in fuel economy, further supporting the theory that there may have been something wrong since day one, but no-one could find it!

I'll be taking this further with BMW and will let you know if I get anywhere... The whole experience from beginning to end has been shambolic, and BMW UK seem impossible to actually talk to directly, passing me back to my local dealer in every instance who I have other concerns about too (it's amazing what a dashcam records when you leave your car with them ;))

DiscoNeil - in light of this I'd be tempted to ask them directly "could this be related to the EGR" and whether or not yours is in the batch you believe may have had an issue .. do let us know if it is ! :)
 

·
Registered
Joined
·
24 Posts
Thanks for the info Rmk, I've had to chase the dealer here who've now booked my car in to do what they call a full software update?, it's not in until 10th of Oct and they have said that BMW are aware of this issue.
While I'm in I will mention the possibility of the egr as you might just have a point with that, I also run a Discovery 3 which had loads of egr issues and in the end I blanked them off and this solved the problems.
I just can't understand why dealers fob off what they do know are known issues, why does it have to get to the point where the customer has to chase them and sometimes even tell them what it might be?
 

·
Registered
Joined
·
1 Posts
My 520d got only 1 week. i've noticed the exact same sound since day 2. Got back to the dealer (in Morocco), but wasn't able to reproduce it. After 2 days the sound came back, so went right away to the dealer, they confirmed that the sound is not normal, left the car for some hours, they adjusted the exhaust tension and said everything is ok. After an hour the sound came back again. Back to the dealer, they have no idea !!!!!
Asked them to contact BMW, which they did, BMW answer: IT'S NORMAL ! :mad
Now, after 7 days, the sound is coming back more frequently, mostly the evening, and it's getting louder.

I will ask them about the EGR and see what they say this time.
Hope you can get more infos !
 
1 - 20 of 84 Posts
Top