[MidnightShadow330]

I had a professional exhaust shop install a VRSF downpipe for my 2021 330i. Everything seemed perfect, with no leaks or anything. However, the other day while on ECO mode on the highway I realized that the car would start shaking like crazy when I tried gradually pressing the gas pedal in the highest gear. This also happens in comfort mode as well. In 8th gear gradually adding gas give me no power and the car shakes intensely. The only way to avoid this is to give it enough pedal force for the transition to downshift to 7th gear. Is this a known issue? Should I be worried about it? Do I have to tune the car for it to go away? What are my options? Thanks.

[Punkwrock]

On my 2020 330i I have had this happen a few times and I was stock. I find the shifting response isn't agressive enough sometimes in comfort and never agressive enough in eco….but I get it, eco should only be used cruising on a highway. But it just puts too much load on the engine. I have never had this issue in sport mode and never in any mode when I was tuned with BM3. Maybe the BMS throttle adjuster could help with this?

Also was there any fitment issues at all with the VRSF? You have the X-Drive and are you in North America?

[VipinLJ]

Sounds like you're trying to lug the engine by gradually accelerating without down shifting. That is bad for the engine. I don't drive in eco mode so I have no idea if the car behaves that way when stock. If it does, it's definitely not good for the engine. You shouldn't try to make the car do that either. Like in a manual transmission car where you slot it into 5th or 6th and the RPM is barely past 1000 and you try to accelerate without down shifting, thereby lugging the engine. Like Punkwrock said, the load on the engine is too much. Probably not an effect of the exhaust.