2018 BMW M760LI judder under light/moderate throttle

[Shahroze]

Hi folks, I'm trying to diagnose a problem I'm having with my 2018 M760LI with 130,000kms

Under light to moderate acceleration, it judders quite aggressively (coming from drivetrain) from 2-5k RPM. The power feels like it's cutting in and out. Under full throttle, there is NO JUDDERING - accelerates as should with no issues.

Things that have already been done top try to fix the issue:

1. Spark plugs
2. All coils
3. Transmission re-flashed and adaptations reset
4. Transmission fluid and filter

The following codes are present:

138104 Exhaust flap, open circuit
180001 Catalytic convertor
138A04 Exhaust Flap 2
180101 Catalytic converter 2


Any guidance?

[jokerswld34]

Seems like you're having issues with the CATS. They are either clogged or you're O2 sensors are having an issue. Do you smell any exhaust gas? Could also be leaks in the turbo / CAT gasket(s)...

As per the exhaust flaps, are they plugged in? Some folks unplug them to get a louder exhaust note in comfort mode.

I would focus on the exhaust system now and see what you come up with.

[finestbm@gmail.com]

Hi
Had the same issue
Try to find this bulletin info

SIB 27 02 20
2020-05-20 JERKING OR SHUDDERING FROM THE DRIVELINE (XDRIVE
TRANSFER CASE ATX13-X)

I changed just transfer box fluid-it fixed my issue

Any question let me know

[finestbm@gmail.com]

I found link to this bulletin

https://static.nhtsa.gov/odi/tsbs/20...76367-9999.pdf

[Shahroze]

Changed the transfer case fluid indicated in the above bulletin - issue is gone. Thanks everyone

[Force Seven]

Hi

I had the same issue and changed the transfercase oil . worked a charm the car is back to normal and smooth

[Derived]

My car does a little bit of this too, almost does feel like it's cutting power but I know it's not, happens under very light acceleration. Will have to see if this fixes it.

[Derived]

After reading this thread again, I'm even more sensitive to what I've been feeling in the car since new. It's actually a bit unsettling, almost like something in the drivetrain is slipping. In fact I've always blamed the brake-by-wire system for making it difficult to come to a smooth, gradual stop - but now thinking perhaps it might be some kickback in the drivetrain related to this issue.

Just to be very clear about what I'm experiencing, hoping that this is what others felt:

A sensation like the tires slipping, axle hop or severe traction control power cutting, also perhaps the occasional very slight sensation that some slack was being taken up in the drivetrain when getting back on the throttle slightly during steady-state driving.

Hoping to get this taken care of soon and will report back.

[m760iM5]

Has the fuel pump been inspected? I hope you've cured this by now.

[Derived]

Fuel pump is fine, as it should be on a car that's only a few years old. Like others, I had the AWD transfer case oil changed, and the symptoms seem to be gone now. Highly recommend anyone who has anything like these symptoms to go ahead and do this. In fact, even if your car doesn't have this issue, it's probably a wise idea anyway, as there's no such thing as "lifetime" oil in any drivetrain component.

[JellyStyle]

is this covered under BMWs warranty if you are OUT of warranty or are you on your own to do it if out of warranty?

[Derived]

I don't think so, it's a TSB and maybe if you throw a fit they might cover some of it but I already had some capital with them I needed to burn on something else so I just paid what they told me it would cost. I believe it was around $300 to have it done.