Drivetrain malfunction... Limp mode. How many things could this be?

[Razor1973]

2012 535i 6MT with ~70K miles and I am getting the drivetrain malfunction error and the car goes in limp mode. I know this could represent TONS of problems and only by looking at the specific codes could one know with certainty, but I'd like to add a few things and maybe someone who really knows this stuff could narrow the issue down to a handful of conditions. I'd also like to know what it would take ($) to correct those conditions if that's something you can guess too.


(A) This has been happening for the past 10K+ miles.
(B) This happens ALWAYS when I start my card cold and I push it just a little bit, like almost nothing. The engine stutters and I get the error and limp mode.
(C) Once the car is hot, this rarely happens, although if I really push it on the highway, it will. It does take a bit of abuse, however. Not much, mind you, but this is definitely more of a cold start problem.
(D) No matter when or why this happens, turning the ignition off and back on right away ALWAYS corrects the problem.
(E) Most times, what happens is the error appears on my screen and the car goes in limp mode and continues this way for as long as I'm driving or even idling, until I stop. Now, this is rare (happened only 3-4 times during these 10K miles), but I've also had the error and chime come on and the car go in limp mode and then, the error continues coming up every few seconds (the car never leaves limp mode), which gets very annoying with the chime... until I stop and start again.
(F) When the car is cold, starting always takes the crank a few cycles. I don't even know if I said that correctly, but the point is that when I first start the car in the mornings, I turn the ignition and the car cranks for about 5 seconds before it starts. This never happens when the car is hot.
(G) The car idles and rides a little rough, but the spark plugs are relatively new.


Feel free to ask anything else you can think of, but does this give you any indication of what could be wrong with my car? I do ultimately plan on taking the car to a BMW shop. I just wanted to see if I could have some preliminary ideas that I can suggest to the mechanics.


Thank you in advance!

[ezaircon4jc]

Battery???

[Razor1973]

Battery doesn't sound likely to me given these symptoms.

[ezaircon4jc]

Battery doesn't sound likely to me given these symptoms.

Dying batteries cause all sorts of electrical issues. Had a car with a dead alternator and dying battery... As I was limping along at ~25mph my tach showed about 6500rpm and the speedo showed 135! Weird things happen in modern, highly electronically controlled vehicles...

[Razor1973]

Dying batteries cause all sorts of electrical issues. Had a car with a dead alternator and dying battery... As I was limping along at ~25mph my tach showed about 6500rpm and the speedo showed 135! Weird things happen in modern, highly electronically controlled vehicles...

True. I will need to consider that one also. Thanks.

[nuck]

Any luck?

[Stück]

You are literally wasting your time, and that of others. Pull the codes to provide a starting point towards diagnosis.

[White94RX]

You are literally wasting your time, and that of others. Pull the codes to provide a starting point towards diagnosis.

+1