Hi folks 

 

just wanted to see if anyone has had any experience with the new M135i xdrive ?,I got mine only a couple of weeks ago and it had done 1k miles when I picked it up ,since then I’ve noticed a tappety noise on fairly decent acceleration,now I know these engine are not the quietest but this is under load ,weirdly can hear it when my window is down but if it’s the passengers you can’t hear it ,so it’s like it’s from the driver side only .Now to see if this was something with my car or maybe a characteristic of the engine ?,I went and drove another at a garage not far from me and it did exactly the same noise !, hence asking on here ,I know dealers will do the old “it’s meant to do tht “ but it doesn’t sound great !!!.thanks in advance .

Morning MT

Welcome to the Forum

My neighbour works for BMW UK and has had one as a Company Car, he tells me it's the Direct Injection injectors and one of the most common queries they get. 

Time will tell I guess, so probably the Dealers will say "they all do that" my personal feeling as an "old Engineer" is it shouldn't!! The AMG A35 doesn't nor does the Audi A3 both simmilar power output.

Dave 

Thanks greydog 

exactly!, like you say time will tell ,that’s why I went to drive another to see if it did the same and obviously it did and both fairly new cars .People are obviously commenting on it to dealers so in the end it will probably get sorted but it makes me wish I had gone done the merc or VW route now ,but it doesn’t seem to effect performance in it as it goes like a stabbed rat 😂

"The reason for the noise level is the extremely high pressures at which the direct-injection fuel system runs. ... Second, the solenoids that control the fuel flow, both at the high-pressure pump and in the injectors, need to be much stronger in a DI engine and are consequently noisier."

Courtesy of:

https://www.caranddriver.com/features/a15146681/skidpads-hydroforming-yaw-control-and-direct-injection-ticking-noise/

 

Thanks suzukiBoy2 

appreciate it 🙌

I understand the explanation of the noise due to the Direct injection pressure's. However is the noise necessary? The engineer in me challenges the response, to me it's almost as though the BMW engineers consider it OK until customers query it then justify it  by saying "direct Injection"?

After all DI has been around on diesel motors for years and they have actually got quieter plus Mitsubishi were producing DI petrol engines late 80's

So how do Mercedes and Audi/VW achieve  a quiet engine that develops the same power ??

Dave

3 hours ago, Greydog said:

I understand the explanation of the noise due to the Direct injection pressure's. However is the noise necessary? The engineer in me challenges the response, to me it's almost as though the BMW engineers consider it OK until customers query it then justify it  by saying "direct Injection"?

After all DI has been around on diesel motors for years and they have actually got quieter plus Mitsubishi were producing DI petrol engines late 80's

So how do Mercedes and Audi/VW achieve  a quiet engine that develops the same power ??

Dave

I wasn't questioning you at all Dave, and I agree with you. There should be, no doubt is, a solution to the noise. I am amazed BMW have yet to solve it.

Morning Richard

My response was aimed at BMW and their Engineers and Marketing guys. They have made some really dumb decisions over the years to list a few, simplex instead of duplex timing chains? Plastic guides? Moving timing chains to the rear of the engine? I know they are not alone this seems to have been a trend but that doesn't make it right. BMW have a loyal following but come on BMW who want's the most powerful tractor in the street !!! If you can make a smooth powerful QUIET diesel do the same with the i35i

Dave