BMW 7 Series Running Rough, Fuel Mix and CEL Issues

Hey there! I have some experience working on BMWs. Had a similar issue with my 2011 BMW 5 Series (also owned a 3 Series before). Those symptoms sound very familiar, I dealt with exactly the same problems. Turned out one of my fuel injectors was faulty, causing uneven fuel delivery. Took it to my regular workshop and they diagnosed it with their diagnostic tools. Had to replace the injector, which set me back about 515 Euro, but it fixed all those issues, rough running, power loss, and the emissions problem. What's your current mileage and have you had any other warning lights besides the check engine? Also, does it run worse when the engine is cold or hot? This info would help confirm if you're dealing with the same injector issue I had.

Thanks for the detailed response! My odometer is at 114067 KM and I just had the regular service done last month. The engine definitely runs worse when cold, especially in the mornings. Only getting the check engine light right now, no other warnings on the dash. Based on what you're describing about your experience, sounds like I might be dealing with the same injector problem. Did you notice any specific symptoms before the injector completely failed in your case? Really want to avoid getting stranded somewhere.

Hey again! Thanks for those extra details. Yeah, that mileage and the cold-running symptoms are exactly what I experienced with my 5 Series just before the injector went completely bad. Before it totally failed, I noticed the symptoms would come and go, some days the car ran perfectly fine, other days it was a mess. The most obvious early warning was this weird hesitation when accelerating from a stop, almost like the car couldn't make up its mind whether to go or not. Also, my fuel consumption started creeping up about a month before things got really bad. In my case, I kept driving it for about two weeks after the first symptoms showed up (probably not the smartest move, looking back). The car never left me stranded, but the running got progressively worse until I finally took it in. The good news is that once the injector was replaced, it was like having a completely different car, smooth as silk again. Since you're seeing such similar symptoms to what I had, I'd suggest getting it checked soon. These injectors usually don't fail suddenly, but why risk it, right? Plus, running with a bad injector can potentially damage other components if left too long. When my mechanic showed me the old injector, it was pretty gunked up, probably from all those cold starts.

Thanks so much for sharing your injector failure experience in such detail. This really helps me understand what I'm potentially dealing with. You're right, I shouldn't risk driving it too long in this condition. Actually, now that you mention it, I've noticed my fuel consumption has gone up these past few weeks too, and I get that exact same hesitation from a stop that you described. I'll call my mechanic first thing tomorrow and schedule it in. Better to fix it now than risk more expensive damage or end up stuck somewhere. Really appreciate you taking the time to walk me through your experience, it's given me a much clearer picture of what's likely going on with my 7 Series. Sound like a pretty straightforward fix once they get to it. I'll make sure to have them check the other injectors while they're at it, just to be safe. Thanks again for all the help!