Drivetrain malfunction" keeps popping up but then disappears
Milesdavenport
I've got a 2017 540i and every few weeks I get that dreaded "Drivetrain Malfunction" warning on the dash. Here's the weird thing though, it usually happens when I'm just cruising normally, not even pushing the car. Then I pull over, restart the engine, and the warning is gone for another couple weeks. The car still feels fine, no loss of power or weird noises. I took it to a general garage and they read the codes but said "could be anything from a boost leak to a software glitch" and wanted to start replacing random sensors. That didn't give me much confidence. I'm looking for an Innovative Malfunction Repair Service that actually knows how to diagnose intermittent issues instead of just guessing. Has anyone else dealt with this on the B58 engine? I'm worried it might be the wastegate actuator or maybe a fuel pressure thing but I really don't want to throw thousands at parts that won't fix it. Also any tips on capturing the data when the error happens would be super helpful. This car has been so reliable otherwise and this one issue is driving me up the wall.
Glyniswaterson
Intermittent drivetrain malfunction on a B58 540i that clears on restart without any performance symptoms is almost always a boost or fuel pressure related fault that only shows up under specific conditions. A general garage reading codes and suggesting random sensors is exactly the wrong approach for an intermittent fault.

Godelivawatkin
Capturing freeze frame data at the moment the warning appears is crucial for diagnosing this properly. If your car has the BMW ConnectedDrive app, enabling the vehicle status notifications can sometimes capture which system triggered the warning before you restart and clear it.

Godivawaveney
Wastegate actuator on the B58 causing intermittent boost faults is a known issue and produces exactly this pattern of warning without obvious performance impact because the fault is brief enough that the engine manages around it. ISTA live data during a drive that triggers the warning will confirm or rule this out.

Goldawaymouth
A specialist with ISTA logging capability can set the car up to record all module data continuously during a normal drive. That log captures the exact moment the fault occurs and shows what every sensor was doing at that instant, which is how intermittent faults get solved without guessing.

Goldieweatherill
Two weeks between occurrences makes replication difficult but not impossible for a specialist who knows how to set up continuous logging. That approach is more expensive upfront than a code read but far cheaper than replacing multiple sensors that were never the actual cause.