Problems after cold start, and stalling out days later

[Dual]

I’ve had stalling problems this morning, 5 days after a difficult cold starting incident. I’m going to list all recent events, although there may be no connection.

In order: new battery, ticking vent fan, disturbing cold-start behavior, hesitations to stall. Outside temps have been kicking around 0ºF for days here.

Five days ago, cold-starting in 0ºF (with a brand-new battery replaced only a few days earlier*), I let the car idle for 4-5 minutes before heading out on a 5-hour drive. First thing I noticed was a ticking in the vent fan system, which still recurs. That’s presumably for another time*.

More importantly, perhaps 10 minutes out, I noticed white clouds coming out of the back of the car as I drove. I thought perhaps it was road salt getting kicked up, or normal vapor, but there was nothing like this visible with other cars. I also started to notice a burning-rubber kinda smell- a bit clutch-like, actually. Eventually the white exhaust stopped. The smell dissipated over a few days.

I pulled over at the next rest stop and noticed black soot around the exhaust. I wiped it off to see if it would continue. Oil level good. No idiot lights. Engine compartment appeared normal. Couldn’t isolate a source for the smell. The rest of the ride home was uneventful, with no more black soot. I called my indie and described all this and he seemed unfazed, welcomed me to come in but didn’t think it was necessary. The car drove normally from then out...

Then, this morning I experienced a string of 2-3 incidents of extreme hesitation leading to stalling. Eventually I was able to restart successfully and drive the 4 miles or so home without incident.

I haven’t had time to pull codes, but I will, and will post here. Meanwhile, I’m putting this out for input from the group. Thank you in advance!


*just being completist.

[Dual]

These errors all cleared. I have a persistent steering angle error.

[wstr75]

I had a similar problem. My steering angle sensor and brake pressure sensors (both brake pressure sensors) were discovered to have non-clearing faults.
Apparently the car's brain seizes up when it has too many of these "dangerous" issues and goes into that darn rough idle, no power, soft brakes operating mode. Like you, I restarted and the car went on to drive normally. I replaced the two brake pressure sensors and had the steering alignment sensor dealt with via alignment. The original problem with the steering angle sensor happened when I changed to a leather steering wheel and did not get the steering wheel back into a proper orientation (this was done by local independent shop).

[Dual]

Absent input here from elders of yet I am strongly inclined to believe that whatever happened that early morning in NY was not directly connected to the stumble/shutdown problems of today. I'd still very much like to know what happened that morning. But this morning- the shutdowns- your input is appreciated. I'm on winter wheels/tires now. I'd hate to align for this temporary, secondary setup.

I've been dealing with a slew of issues probably involving the SAS: adaptive steering broke after I swapped LCM's and I've been going through hell trying to get things back to working order. SAS fault codes that won't clear are a new part of it. It's the dead of the coldest winter in decades, LOL...

[slater]

These errors all cleared. I have a persistent steering angle error.

have you tried recalibrating the SAS? do it twice in a row. i had an issue with one not holding a calibration for more than a day, and did it twice in a row and it hasn't come back yet - this was about a year ago. of course, now that i mentioned it, it will come back...

as for the other codes above - could very well be the CPS being intermittently faulty, as it would trigger a misfire code. a bad plug or coil pack would not trigger a CPS code, however.

It's the dead of the coldest winter in decades, LOL...

that's when stuff always breaks...

[Dual]

have you tried recalibrating the SAS? do it twice in a row. i had an issue with one not holding a calibration for more than a day, and did it twice in a row and it hasn't come back yet - this was about a year ago. of course, now that i mentioned it, it will come back...

Thanks: I will definitely look into this. Trying to reach the local guy who has complete BMW service software. Or could I do it in PASoft??

as for the other codes above - could very well be the CPS being intermittently faulty, as it would trigger a misfire code. a bad plug or coil pack would not trigger a CPS code, however.

Again, thank you. I'll be following up on this.

[slater]

Thanks: I will definitely look into this. Trying to reach the local guy who has complete BMW service software. Or could I do it in PASoft??.

yep, you can do it in PASoft. go into the SAS module and then there's a recalibration option.

[Dual]

Thanks! This has been a seriously big help.

I presented a bunch of problems here in large part because I was uncertain about the interconnections between events. I'm still wondering what happened a week ago, with the smoke/vapor and the soot around the exhaust.

Ideas, anyone?