2 hours ago
Okay so my 2017 540i has been throwing that dreaded "Drivetrain Malfunction" message every few days, but here's the weird part – sometimes a simple restart makes it disappear for a week, other times it goes into limp mode right when I'm merging onto Sheikh Zayed Road. I've already changed the spark plugs and coils because that's what everyone suggests first, but no luck. Took it to two different garages and got completely opposite answers – one said low fuel pressure, another said bad vanos solenoid. I'm burning money just on diagnosis fees at this point. What I really need is a place that does fast problem diagnosis without just guessing and throwing parts at it. Has anyone dealt with this intermittent nonsense on a B58 engine? I love the car when it works but I'm losing confidence taking it on longer trips to RAK or Fujairah. Also curious if a proper scan with ISTA would show something generic OBD scanners miss. Any advice from someone who's actually solved this would save my sanity.