Engine shut during stop sign
 

So usually when driving in between stop signs in LA, I have a light foot. If I maintain 30ish-MPH the gear tends to change really rough to 3rd, unless I gas it a little more. But today for the first time, I ended up coming to a stop right when it changed to 3rd and the engine stalled. I had to start the car and everything was normal.

I have an automatic trans. I'm only assuming that it is changing to 3rd, but not really sure since it's auto.

How long has this been happening for? Does the X start to shutter and shake when it slows down; almost to the point the engine is losing fuel, engine shakes, then stalls?

I don't remember it shuttering or shaking upon stopping. However, during cold starts I do feel the shuttering and shaking 10-secs. into the initial start. But the s/s only last a few seconds and goes away, i have just been assuming this is normal. Dealer always can't replicate symptom, so I don't know what to do with them.

This is the first time my X has stalled. The way it transitions into the stall was similar to how manuals do when you change gear w/o enough revs. But I just didn't think it was normal that in an auto, it would do this. Thanks for the input!

Same thing happens to me.
 

Were you able to figure out what happened with your X5? My X5 4.4i 2005 has shut down at a couple stop lights, the driveway, and stop signs. A couple things to note. This has never happened while in motion. Never in sport mode. All after filling up at Costco.

I called our local dealership and the first question the service guy asked was, "where do you fill up for gas?". I told him usually Chevron and sometimes Costco. He said stay away from Costco gas because of ethanol content.

This has all happened on the same tank of Costco gas (probably about 7 times in the last 2 weeks). My plan is to drain this tank and then fill up at either a chevron or someplace that contains 0% ethanol. My brother and parents are previous X5 owners and they're telling me it's the cam sensor.

Any thoughts?