I recently developed a surging "issue" that shows up during low engine speed, part throttle operation. Happens mainly in non-sport mode. Sport mode masks it a little, but it is still there.

What are the symptoms of the wastegate actuator starting to wear? Will it show as max boost issues, or as boost control issues? It seems that if I go wide open throttle and drive like a maniac, I don't get any surging. But if I try to drive conservatively, i'll get a surging power delivery.

Hope that makes sense. Ask me questions if you want more information.

 

I decided to do some troubleshooting yesterday. Took apart my PCV on the cam cover, cleaned it up, and put it back together. This morning, car ran pretty smooth, without any surging like it had previously. Since cleaning the PCV diaphragm helped, I will likely purchase a new diaphragm and clean up the PCV even better.

For reference, I followed the instructions and guides in this thread:
https://www.northamericanmotoring.co...-question.html

 

I have the same issue on my F56 MCS stick. Happens most noticeably at 80mph up hills in eco, less in mid, and less still in sport.

Interesting the PCV helped. I'll try that this weekend when I do the oil change.

Also going to hook up my OBDII meter and see if throttle is fluctuating. I'm leaning on the pedal sensor, but that's not based on any facts yet.

I'll keep you posted on progress.

 

Thanks for bumping this thread. My car still has the part throttle surging issue. I am not convinced it is related to the PCV diaphragm, but can't say with 100% certainty.