Surging at 58ish MPH
 

Good morning all,

I have a 2013 35d. I've noticed over the last few weeks that if I am at partial throttle around 57-60mph there is a noticable hesitation/surge (think of a wave of throttle input). I have no CEL, I pulled codes and there is nothing there. I'm having no acceleration issues, starting issues, mpg's are right where they should be and have no issues shifting.

Could it be a non engine/trans issue? Possibly a damaged CV or out of balance tire?

Any ideas would be appreciated.

I don't have a diesel, but have an E60 535i that was surging as well. The intake ports were all gunked up from the direct injection backflow into the ports. Seems to be common on the DI/turbo motors. Have you checked the swirl ports? I think they get caked up and cause drivability issues.

Following.

My wife and I noticed this same surging last weekend. I too own a 35d, but a 2009 model.

Swirl flap issue.....interesting. I'll dig into that for sure. I've taken the top end of 35d's apart so many times I can practically do it in my sleep. lol