[AxisF80]

Hey guys. Looking for some help in diagnosing a problem. 2008 e90 M3 with just shy of 50,000 miles on it. My wife was driving the other day and got the following error messages:

Engine malfunction! Reduced power
Increased emissions!
DBC malfunction! Drive carefully
Start-off assistance inactive!
DSC malfunction! Drive carefully

The car went into limp home mode and wouldn't rev over 3k or so with very little power. She pulled over, restarted, check engine light remained along with increased emissions but it ran fine. I took it out to replicate and sure enough same thing happened to me. The car was fully warmed up and when I aggressively pulled out onto the highway, I had the same error message and loss of power. I used my cheapo obd reader and it showed code P0638. I reset the SEL and brought it home.

I have been reading up on various errors on here for a while now and I'm still very unsure. I first focused on the DSC malfunction because that is what my wife mentioned on the phone. Even after the warnings popped up, the turn signals turned off appropriately, so I don't think the steering angle sensor is bad. My next thought was wheel bearing as I have noticed a ticking coming from the front left wheel.

But would a wheel bearing/speed sensor problem also cause an engine malfunction/limp home mode? Would the BT tool show a bearing code or speed sensor code? (Not that I have access to one).

Perhaps the rough idle SIB problem but would that trigger the DSC warnings? Any help would be appreciated.