Pebraun
BMW Z4 Won't Start: Trans Issues & Mechanic Trust Crisis
Car won't start
Fault stored
Transmission slips/shifts erratically
Check engine light on
4 comment(s)
Thanks so much for sharing your experience! Really relieved to hear someone else went through this. My car's been giving me some serious stress lately, and hearing that you got yours sorted out is super encouraging. Quick question, do you mind sharing roughly how much you ended up paying for the whole repair? Also, have you noticed any other quirks or issues pop up since getting it fixed?
Hey again! Really glad my previous reply helped! Just wanted to update you, after taking my car to the specialist mechanic I mentioned, they confirmed it was exactly what I suspected: the transmission control unit was the culprit. The total repair came to 1000 € to replace and reprogram the faulty unit. Worth every penny though! Since getting it fixed, my car's been running like a dream, especially that parking position that was giving me grief before. No more starting issues, and the transmission shifts are butter-smooth now. Haven't had a single problem in the months since the repair. Honestly, I was worried at first about the cost, but considering how essential the transmission is, it was money well spent. Plus, it's way cheaper than having to deal with a completely failed transmission down the line! Just make sure you get it sorted soon, these issues tend to get worse if you leave them too long. Feel free to ask if you need any other info about my experience with the repair!
Thanks for all the details! I actually just got back from the mechanic today and wanted to share my experience. Turns out you were spot on, it was the transmission control unit causing all the trouble. The certified specialist I found diagnosed it right away. The repair was pricey but worth it. I was scared it would be worse, but the final bill was actually less than what you paid, around 850 € including labor. The mechanic I found was super transparent about everything, showed me the faulty part, and explained what they were doing every step of the way. Such a relief after my previous bad experiences! The car's running perfectly now, no more rough shifts or starting problems. Feels like I got a new car honestly! Really grateful for your advice about going to a specialist. You saved me from potentially making the wrong choice with a regular mechanic who might've just made things worse. Keeping my fingers crossed it stays this way, but feeling much more confident now. Thanks again for all your help!
Hey there! I had nearly identical symptoms with my 2015 BMW M235i last year. The transmission control unit was failing, causing similar starting issues and rough shifting patterns. Initially thought it was the parking lock too, but diagnostic tests revealed it was more complex. Got it fixed at a shop specializing in German cars, it was definitely a serious issue that needed immediate attention. The faulty control unit was affecting multiple systems, including the engine management. Left untreated, it could've led to complete transmission failure. The repair involved replacing the transmission control unit and reprogramming the system. My car's been running smoothly since then, no more rough shifts or starting problems. My advice: Don't wait on this one. Find a certified BMW specialist, they'll have the right diagnostic tools and experience with these specific transmission issues. The symptoms you're describing are too similar to ignore, and it's not something you want to risk with a non-specialist. Hope this helps!