BMW Z4 ASC & ABS Issues: Acceleration Problems Troubleshoot

Hey there! I have some experience working on BMWs, and your issue sounds very familiar. I had a similar problem with my 2003 BMW 3 Series (325i) last year. The symptoms were exactly the same, ASC and ABS warnings, plus that annoying jerking during acceleration. After a bit of back and forth with my mechanic, we found out it was a faulty ASC relay. Got it replaced, and it cost me around 90 Euro, totally worth it as it fixed all the issues immediately. Haven't had any problems since then. Before I share more specific details about what my mechanic did, could you tell me if you've checked the fault codes? Also, what engine variant does your Z4 have? Knowing these details would help me give you more relevant advice from my experience.

Thanks for sharing your experience! My Z4 has been pretty reliable up until now (152049 KM on the clock). Just got it serviced last month, and everything was fine then. Haven't pulled the fault codes yet, but I'll definitely get that done ASAP. Mine's the gasoline version, and your relay suggestion makes a lot of sense given the symptoms. Really encouraging to hear you got yours sorted without breaking the bank! Did your mechanic mention any other potential culprits I should keep an eye out for while I'm at it?

Hey again! Glad to help further. Yeah, when I had this issue with my 325i, my mechanic actually did mention a few other potential causes we should check. While the relay was the culprit in my case, he said it could also be related to the wheel speed sensors or the ABS control module. In my case, before we pinpointed the relay, we checked the wheel speed sensors because they're a common failure point, they can get dirty or damaged and cause similar symptoms. My mechanic also mentioned that corroded connections in the ABS module can cause these issues, though that's usually a more expensive fix. Since your Z4 just had a service, it might be worth asking if they noticed anything unusual with these components. My 325i had about 160,000 KM when this happened, so pretty similar mileage to yours. I'd definitely recommend getting those fault codes read, that's what really helped us narrow down the issue in my case. One thing I learned through this whole experience: don't wait too long to get it fixed. I drove around with the warning lights for a couple of weeks before getting it sorted, and the jerking during acceleration only got worse. Better to tackle it sooner rather than later!

Thanks for that detailed follow-up! Really appreciate you sharing all those potential issues to look out for. I'll definitely get those fault codes read first thing tomorrow and check with my recent service center about any notes they might have made about the sensors or ABS module. You're absolutely right about not waiting too long, I've noticed the jerking is getting a bit more pronounced, especially during my drive this morning. The fact that your BMW had similar mileage when this happened is quite interesting. I guess these things often crop up around the same time. I'm hoping it's just the relay like in your case, that would be the best-case scenario cost-wise! Will make sure to ask my mechanic to specifically check the wheel speed sensors and connections too, since you mentioned those can be trouble spots. Thanks again for taking the time to share your experience, it's really helped give me a clear direction on what to investigate. I'll make sure to get this sorted quickly before it potentially becomes a bigger issue!