Car shuts off after 15 seconds.

[DameJ.M3]

My 2011 M3 6MT random stalled out on me while I was pulling away from a stop light (I was already off the clutch completely going about 10-15mph). The car suddenly lost power, I was literally putting my foot to the floor and the car didn't react. I noticed the rpms started to fall so I put my foot on the clutch trying to get the car moving again. Unfortunately it just stalled out. I tried to restart the car but nothing happened when pressing the start button. Just one click noise of the valves opening I believe or the starter motor. Being on a really steep hill I tried to pop start it and of course the car started but would just shut off a few seconds later.

I then had the car towed home and fast forward a few days later (when I found the time to diagnose the car). the codes I originally pulled were as follows.

I then tried to spend the rest of the day looking up the codes and what causes them. Also if anyone shared this tragedy. Not much luck there and almost all similar tragedies led to either rod bearings failure or main bearings failure.

A few days later and I go out and decided to try and start the car so I can try and move it to my garage (the tow truck driver placed the car in a very inconvenient spot). Surprisingly the car fired right up and idled for almost 30 seconds before it went into limp mode and shut off. Now I found it weird that the car could even start since before it wouldn't. I then restarted the car with no issue and I drove it into my garage. The car shut off about every 15 seconds but eventually I got it in there (I know this is probably very bad but being alone and needing my car in the garage to properly work on it I made the choice).

Now is when it gets very weird. After doing some more diag I narrowed it down to possibly be my o2 sensor. Bank 2 to be exact. So I had the idea to quickly jack up the front of my car and check the sensor for damage. It was at the time I remembered I could use the bitflash scanner I have with my tune to read the codes. I then removed my tune and scanned the codes

I then started my car and surprisingly it stayed running. I then assumed maybe it's my o2 sensor and the car just couldn't run properly with the tune and bad o2 sensor. So I lowered the car on the jack so I could move it over a bit and get it on the lift to get better access to the sensors. The second my car came off the jack it choke and stalled out.

Now I'm really confused on what could be causing this issue.

[msan]

not sure, but if you are handy maybe try switching the bank2 o2 sensors with bank 1 and see if the code follows the sensor?

[deansbimmer]

Test your battery and alternator.

[DameJ.M3]

Was following up on the bank 2 sensors I was getting codes for and I found this ground cable. I believe it may be the issue. When unbolting the under cover I noticed a spark when the final screw came out.
So my next question is does anyone know the part number or where I can get one of these ground cables?

[GORDON.M3]

Originally Posted by DameJ.M3

Was following up on the bank 2 sensors I was getting codes for and I found this ground cable. I believe it may be the issue. When unbolting the under cover I noticed a spark when the final screw came out.
So my next question is does anyone know the part number or where I can get one of these ground cables?

Ouch that ground cable is done!

Check this thread out if its the same one.
https://www.m3post.com/forums/showthread.php?t=1444544

[DameJ.M3]

Originally Posted by GORDON.M3

Ouch that ground cable is done!

Check this thread out if its the same one.
https://www.m3post.com/forums/showthread.php?t=1444544

Originally Posted by GORDON.M3

Ouch that ground cable is done!

Check this thread out if its the same one.
https://www.m3post.com/forums/showthread.php?t=1444544

Yup it's that same one. Thank you.

[odman99]

I just want to say thank you

You saved me so much trouble, it was the ground cable

Under the car, after a track day. Legit was about to pull the engine, had all ignition coil codes.