N55 rattle/tapping noise under load

[PropAviator]

This post is regarding a 2016 35i M sport (x drive) and a very annoying noise that recently began. I purchased the vehicle as a CPO in Dec 2018 with just over 30k on the clock. It has been a great vehicle only needing tires, brakes, wiper blades, a battery and some minor warranty repairs during my ownership. CPO warranty in effect through 12/31/2021.

Within the last 2 months, a noise that is best defined as a rattle/tapping sound has become progressively louder. The noise is not present during idle rpm and while the vehicle is stationary. While accelerating from a complete stop, the popping/tapping/rattle begins and is sporadic. As engine speed and driveline speed increases, the tempo and volume of this noise commensurately increases. When moving with no throttle input the noise is not present. The only way to replicate this noise is with the engine and driveline under load.

At my first visit to the dealership for this "noise", I drove the car with the shop foreman and replicated the noise characteristics. The result = They replaced the torque converter. This made no difference as when I drove out of the service drive the noise was apparent. After a road trip to Northern AZ last week, the noise was exponentially louder and definitely attracted the attention of pedestrians. I took the car back, replicated the same noise for the same shop foreman and dropped it off.

My service advisor called yesterday stating the car was ready and there were no anomalies detected. He said the techs consulted with BMW Engineering and the noise was deemed to be a "normal" characteristic after the engine accumulates some time in service (See attached doc from BMW).

I will post a video with the sound for reference when I am able. Has anyone else had a similar experience?

[sukhk527]

I had a similar issue. Seems to be more prominent when driving against a wall on the drivers side yea? Was told it's just loud injectors and so on and the acoustics are just how that is. Hasn't been a problem for me at all.

[tlow98]

I might have this too. Does it sound like a loose exhaust shield? That's what mine sounds like.

Not loud, doesn't bother me

[PropAviator]

tlow98: Yes, it does sound metallic and something like a loose exhaust/heat shield. I initially thought it was something of that nature.

sukhk527: Definitely more noticeable when driving close to a wall etc.

[dubs]

I had the same metallic rattle and it completely went away after dealer replaced the turbo something about a flap causing the noise. To be more specific it only made noise under acceleration most noticeable around 2-3k rpm while the car was fully warm didn't make any noises when car was cold usually took me about 10-15 minutes of driving from a cold start to then start hearing the tapping. I could replicate the noise even while parked keeping revs back and forth between 2-3k while car is fully warm.

[BeachsideF30]

Originally Posted by PropAviator

tlow98: Yes, it does sound metallic and something like a loose exhaust/heat shield. I initially thought it was something of that nature.

sukhk527: Definitely more noticeable when driving close to a wall etc.

I'm having this same issue on mine too. It only does it once warmed up or close to being warm not being cold and only under load 2-3k. It doesn't do it while under hard high rpm acceleration but just casual very light gas and load. At first I thought it was an issue with my MPE install but couldn't find any leaks or anything loose at all. This is my 4th bmw and I've never heard this metallic tapping/fluttering. I could hear it quite predominantly one day when my wife left a parking lot and I was outside. I was going to bring it up at my next service. It will be interesting to see if other have this issue as well.

[BeachsideF30]

Originally Posted by dubs

I had the same metallic rattle and it completely went away after dealer replaced the turbo something about a flap causing the noise. To be more specific it only made noise under acceleration most noticeable around 2-3k rpm while the car was fully warm didn't make any noises when car was cold usually took me about 10-15 minutes of driving from a cold start to then start hearing the tapping. I could replicate the noise even while parked keeping revs back and forth between 2-3k while car is fully warm.

What was the process or the diagnosis of them relaxing the turbo for this? Cause for me if I load it stationary 2-3k I don't have it or if I rev it in the driveway. It's only while moving, and it fluctuates with rpm which is even stranger

[dubs]

Originally Posted by BeachsideF30

What was the process or the diagnosis of them relaxing the turbo for this? Cause for me if I load it stationary 2-3k I don't have it or if I rev it in the driveway. It's only while moving, and it fluctuates with rpm which is even stranger

Yea it fluctuated for me as well rattle would start slow then get fast as rpm went higher. The metallic rattle was pinpointed on park by standstill revving at 2400 rpm then hitting the gas hard past 3k rpm I could barely here it from my car but was more pronounced with someone listening from under and this was when car was fully warm maybe after driven 20 minutes. I made numerous videos from cruising late night next to a highway divider, driving between parked cars and driving in a indoor garage also made same scenario videos of my friends F15 that has 80k miles which made no noise at all. I showed the videos to a master tech while also going on a test drive and he knew right away saying that its highly likely coming from my turbo or possible catalytic converter. After couple of days it was confirmed coming from wastegate flap of turbo and replacing the flap alone wasn't an option so entire turbo was replaced.

[MohDarawsheh]

Originally Posted by dubs

Yea it fluctuated for me as well rattle would start slow then get fast as rpm went higher. The metallic rattle was pinpointed on park by standstill revving at 2400 rpm then hitting the gas hard past 3k rpm I could barely here it from my car but was more pronounced with someone listening from under and this was when car was fully warm maybe after driven 20 minutes. I made numerous videos from cruising late night next to a highway divider, driving between parked cars and driving in a indoor garage also made same scenario videos of my friends F15 that has 80k miles which made no noise at all. I showed the videos to a master tech while also going on a test drive and he knew right away saying that its highly likely coming from my turbo or possible catalytic converter. After couple of days it was confirmed coming from wastegate flap of turbo and replacing the flap alone wasn't an option so entire turbo was replaced.

Hi My dear,

Did it like this noise at second 7?

[AW0802]

I have the same issue and I had replace the rob bearing and the taping noise still there, until last week when I change my oil change, I put a bottle of Liqui Moly Ceratec in it and that taping sound is gone,I had drove about 800 miles so far so good, dont ask me how cause I dont even know how, FYI: I been using Luqui Moly 5W30 Special Tec B FE Engine Oil the whole time of ownership, and this is my first time using Ceratec on this car.

[Dhillon.F15]

I have a 2018 bmw x5 and I have a similar issue have you found the cause/fix.

[irzayev]

The same problem on my X5 2017 Xdrive 88000km.
I have 2 versions:
1. Wastegate
2. Transfer case or smth near.

Strange is that the noise is only in load, only on hot engine...

I calibrated VTG, calibrated Wastegate, noise still exists...

[F15_SGM]

Liqui molly is the best. All the other oil brands engine is louder. Throw some mos2 it will keep it nice and new

[tlow98]

It should be noted that more than a few people have solved this by adding liqui moly ceratec engine treatment. It doesn’t take a lot of sense but I’ll be trying the same soon. Why not for $25

[jamal.is.in@gmail.com]

Originally Posted by MohDarawsheh

Hi My dear,

Did it like this noise at second 7?

I have same sound that started recently. Did you figure out what’s wrong with it ?
I can hear only when windows are down.

[tlaspec]

there is another thread over 3-4 years and no one is able to pin point root cause. However, therr are recent success with adding liqimoly ceratec additive with some members.

[SeeYa]

Originally Posted by PropAviator

This post is regarding a 2016 35i M sport (x drive) and a very annoying noise that recently began. I purchased the vehicle as a CPO in Dec 2018 with just over 30k on the clock. It has been a great vehicle only needing tires, brakes, wiper blades, a battery and some minor warranty repairs during my ownership. CPO warranty in effect through 12/31/2021.

Within the last 2 months, a noise that is best defined as a rattle/tapping sound has become progressively louder. The noise is not present during idle rpm and while the vehicle is stationary. While accelerating from a complete stop, the popping/tapping/rattle begins and is sporadic. As engine speed and driveline speed increases, the tempo and volume of this noise commensurately increases. When moving with no throttle input the noise is not present. The only way to replicate this noise is with the engine and driveline under load.

At my first visit to the dealership for this "noise", I drove the car with the shop foreman and replicated the noise characteristics. The result = They replaced the torque converter. This made no difference as when I drove out of the service drive the noise was apparent. After a road trip to Northern AZ last week, the noise was exponentially louder and definitely attracted the attention of pedestrians. I took the car back, replicated the same noise for the same shop foreman and dropped it off.

My service advisor called yesterday stating the car was ready and there were no anomalies detected. He said the techs consulted with BMW Engineering and the noise was deemed to be a "normal" characteristic after the engine accumulates some time in service (See attached doc from BMW).

I will post a video with the sound for reference when I am able. Has anyone else had a similar experience?

Yes, same exact experience (2019 X6 35i) and they gave me the same bulletin. I posted about it here last week.

[phipark]

I had a similar issue. A slight tick that you could hear against a wall. Just poured in the LiquMoly Ceratec and I think it's gone. Just like that. I'll give it a few more weeks, but so far I'm shocked. All I can hear now is the rubber grinding on the concrete.

[neverdone]

Originally Posted by phipark

I had a similar issue. A slight tick that you could hear against a wall. Just poured in the LiquMoly Ceratec and I think it's gone. Just like that. I'll give it a few more weeks, but so far I'm shocked. All I can hear now is the rubber grinding on the concrete.

I've got the same issue. Gonna try some liquimoly today, see what happens.

[tlow98]

Originally Posted by neverdone

I've got the same issue. Gonna try some liquimoly today, see what happens.

Please report back for everyone’s benefit :-)

[BeachsideF30]

When we go to sell these F15s we can only pray they test drive with the windows up lol

[neverdone]

Originally Posted by tlow98

Please report back for everyone’s benefit :-)

Well apparently in my town, no one knows what it is lol when im home ill get to the city and get a bottle and report back.