BMW X7 Engine Jerks: Bad Fuel Injectors or ECU Issue?

Hey there! I had a similar experience with my 2019 BMW X5 40i last year. The symptoms you're describing match exactly what I went through after getting a third-party chip tune. The jerking, power loss, and check engine light were all present in my case. After multiple diagnostic sessions, it turned out the tune had messed with the engine management system and caused some serious issues with the fuel injection timing. The solution required a complete reset of the ECU to factory settings and reprogramming by certified techs. It wasn't a quick fix, my car was in the shop for nearly a week. My advice? If you've had any engine modifications or tunes done, mention this upfront to the mechanic. These symptoms often point to electronic/software issues rather than mechanical problems. I'd strongly recommend going to a certified BMW service center for this particular issue, as they have the proper diagnostic tools and access to factory software. The repair was definitely on the expensive side, but it resolved all issues completely. No problems since then, and I learned my lesson about third-party tuning.

Thanks for sharing your experience! That definitely sounds similar to my situation, though I haven't done any tuning or mods on mine. Good to know about the fuel injection timing possibility. Hey, do you mind sharing what the final bill came to? And have you had any other problems with your X5 since they fixed it? Just trying to get a rough idea of what I might be looking at cost-wise and if I should expect any related issues down the road.

Hey again! Good news, everything's been running perfectly smooth since I had that issue fixed. Turns out you were right to ask about the costs, I got off relatively easy at 180 € since it was mainly just reversing that dodgy third-party chip tune that caused all the trouble. The mechanic found the fault code was directly linked to that tune job, classic case of getting what you pay for, I guess! My X5's been purring like a kitten since the repair, honestly not a single problem in that department. The certified techs really knew their stuff. They basically reset everything back to factory settings, and it's like having a brand new car again. Since you mentioned you haven't done any mods, your issue might be something different though. But at least in my case, getting it sorted at a proper certified place was worth every penny. They gave me a full diagnostic report and everything, really professional job. Would you believe I actually considered going back for another tune? But nah, lesson learned, keeping it stock from now on! The car's got plenty of power anyway when it's running right.

Thanks for all that detail! That's actually a relief to hear your repair cost was reasonable. I bit the bullet and took my X7 to a certified shop yesterday. Turned out to be a faulty fuel pressure sensor causing all the drama, way less complicated than I feared! Bill came to around 300 for parts and labor, which honestly isn't too bad. The mechanic I found was super thorough and professional, explained everything before starting the work. Such a different experience from my last mechanic who always seemed to find extra problems to fix. Car's running beautifully now, no more jerking or power loss. The shop even gave me a detailed report showing all the diagnostic tests they ran. Amazing what a difference finding the right mechanic makes! Really glad I asked here first instead of going back to my old guy. Funny how we stress over these things and sometimes they turn out to be simpler fixes than expected. Thanks again for sharing your experience, helped me make the right call on where to take it!