[a77cj7]

I have a 2016 m235i xdrive with 90k miles. Completely stock except for a BMS Stage 1 added when I bought it at 25k.
Since 70k miles or so, I have had an intermittent cold start issue where it cranks longer and sputters. Once it starts, everything is normal.
No CEL.
I replaced plugs and coils at 75k and the battery recently. Both seemed to fix for a week then the issue returned.
Lately the issue has gotten to be almost every cold start and much more pronounced. I am concerned it may fail to start.
I have no BMW dealer within 300 miles.
Can anyone help me diagnose this issue? I have a video, but am unsure how to upload.

Thanks,
Chris

[LA1Z24]

Leaking injectors.

Hook up a scan tool that can GRAPH data. Graph the FUEL RAIL PRESSURE SENSOR. Let the engine idle and get hot. Shut the engine off, but key on quickly so you dont lose data communications. Does the fuel rail pressure raise or drop? If it drops you need new injectors. If it raises, up to 1000psi sometimes, you are golden and time to look elsewhere for your issue. But this is probably your issue. Change them in a set of 6.

[a77cj7]

Leaking injectors or a failing check valve was my suspicion as well, just from general automotive experience.
I didn’t realize these cars monitor fuel pressure. I have bimmerlink with obd2 dongle, I believe that will display the pressure real time. If not, I will find a scanner that can do it.
If it is losing fuel pressure, I’m not sure how fast. It has no issue with hot starts.
I am out of town for week, but will report results this weekend.

Thanks,
Chris