[Blackdog76]

I thought I’d post this as a warning. I was driving my 2011 335d with the wife and kids in the car at normal freeway speed in the fast lane going uphill and the crank sensor failed. I lost all engine power in an instant and had to cross 4 lanes of traffic and find a piece of shoulder to pull over. It was a miracle that I didn’t get hit in the process and that small section of shoulder was there because it’s mostly a 1 foot shoulder and a guard rail along that stretch of the 101.

I tried restarting the car and the starter would crank for a few seconds and then give up. NO codes!!! I tried restarting until the battery got too low.

Ryan at BRR tuning helped me diagnose the crank sensor since there was no RPM reading on the tach when cranking.

I replaced the crank sensor and have around 800 miles on it since. Everything is all good now with the D but my daughter is still fairly traumatized from half the cars on the freeway smashing into us all at once.

I was able to replace the sensor without removing the intake. It takes a lot of extensions and removing a few guards below but worth it in my opinion.

My advice is this, if you are around the 100k mark, replace it.

[BB_cuda]

Thanks, Blackdog76. Sounds like you're a Led Zep fan :-D

[Owen81]

Did the sensor fail or was the pickup magnet covered in metal shavings?

[Blackdog76]

No metal shavings, the sensor looked perfect externally

[lnxguy]

Common problem. Key is no rpm when cranking.

[e90Noobie]

Where exactly is this sensor located? Pics would be nice.
Thanks

[335dlci]

Originally Posted by e90Noobie

Where exactly is this sensor located? Pics would be nice.
Thanks

Under starter.