I have an R52 Convertible S. Intermittently, I will be at a stoplight, and when I go to accelerate, the vehicle will start to move forward, but drop RPMs as if there is insufficient gas going to the engine. Then, it will surge. The problem persists a few times, then it goes away entirely, and I will drive normally. This happened last week, where I had issues gaining RPMs at first acceleration; everything had been functioning properly prior. It happened again last night. The vehicle does not go to zero RPMs—it idles fine, so I never know if it is going to occur when I am about to move forward. In both cases, I let the vehicle rest for abt 30 minutes, then went about my night as usual with zero further issues.
I do delivery driving, so since I have purchased the vehicle, I have put a solid 7,500 miles on it in about five months; I need this to be functioning properly.
I am aware of issues with the R56 and fuel pump relay on the main circuit board. However, I have the R52 and cannot connect the issues.
Any thoughts?

 

I'm assuming there's no Check Engine Lights? It kind of sounds like the issue pops up when it gets hot. Then after 30 mins, it cools down enough to run normal. It makes me think there could be a slight crack in one of the intake vacuum lines that expands when it gets hot, allowing air to leak, then closes when it cools.

https://www.realoem.com/bmw/enUS/sho...diagId=11_3788

 

Thank you for this, and it's interesting that you said this. I just replaced my air intake hose on Sunday. The initial hose had a crack in it—and likely the issue. I noticed improved performance. The PO was elderly and I think she got around never realizing this thing was due for lots of little parts needing replaced.
I'm not familiar with any of the intake vacuum lines that might expand. Since Sunday, when I swapped out the air intake hose, I bought myself a smoke tester so I can see what the integrity of the entire system is like. It's very likely by changing the air intake hose, I fixed the issue. But, I want to ensure that 100%.