BMW 5 Series Jerking and High Fuel Use, Need Diagnostic Help

Hey there! I had very similar issues with my 2003 BMW 3 series last year. The symptoms were almost identical, sluggish acceleration, jerking, and higher fuel consumption. Turned out to be a faulty fuel injector. Had it diagnosed at the garage, and the scan showed injector problems on cylinder 2. The injector was stuck partially open, dumping too much fuel into the cylinder. This definitely explained the rich condition and poor performance. They had to replace the injector and clean the others as preventive maintenance. It was quite a serious issue that needed immediate attention, running too rich can damage your catalytic converter over time. From what you're describing, I'd strongly suggest getting those injectors checked soon. The symptoms are textbook injector failure. Best of luck sorting it out!

Thanks so much for sharing your experience! This really sounds exactly like what I'm dealing with. It's a relief to hear someone had the same issue and got it fixed. Would you mind sharing how much the repair ended up costing you? Also curious if you've had any other problems pop up since getting it fixed? I'm planning to take it to a shop this week and want to have a rough idea of what to expect cost-wise.

Hey again! Happy to update you! Since you asked, I got it all sorted and it cost me 515 € to fix the faulty injector. They found one injection valve was definitely bad and needed replacing. Pretty much exactly what I suspected when I first replied to your post. The best part? The car's running like a dream now! That rich fuel mixture issue is completely gone, no more jerking, no more excessive fuel consumption, and the engine response is back to normal. It's been about 6 months since the repair, and I haven't had a single problem pop up. I know the repair cost might sound a bit steep, but honestly, it's worth every penny to prevent further damage to your catalytic converter. Plus, the fuel savings alone make a difference, I'm not burning through fuel like before. If you're heading to the shop this week, I reckon you'll be looking at something similar cost-wise. Just make sure they properly diagnose which injector is faulty, in my case, it was definitely worth paying for the thorough diagnostic work. Let us know how it goes at the shop!

Just wanted to update everyone, I took my car to the mechanic yesterday! You were spot on about the injector issue. Turns out I had two faulty injectors that needed replacing. The total came to about 800 € for parts and labor, which was a bit more than I expected, but the difference in how the car runs now is incredible. The mechanic I found was actually great, super transparent about everything. They showed me the old injectors and explained exactly what was wrong. The diagnostic process was thorough, and they even cleaned the remaining injectors while they were at it. Took it for a drive after picking it up, and wow, it's like having a different car! No more jerking, the acceleration is smooth again, and the engine light is finally off. Already noticed the fuel gauge isn't dropping as quickly as before. Really appreciate everyone's input, especially about getting it checked quickly. You helped me avoid what could've been some serious damage to my catalytic converter. Thanks again for all the helpful advice!