Seen stuff like this a few times over the years including on my old 323. Hard to diagnose till you get codes. Personally, when things like this happen I just wait till it craps out again and throws a code. But if you really want to go "huntin" for the problem here are the common things to check.
1. Fuel pump. Rent a fuel pressure gauge and test at the access port on the fuel rail.
2. Coil packs and boots. Test them for spark by removing one at a time and arc it to a screwdriver or something. Be careful! 3. Get a scanner that shows what your 02 sensor voltage and if they are within spec
4. Check spark plugs. Are they oily, black, white? They'll tell you how your engine is running
Those are some easy and cheap ways to get started
Sent from my One X using Bimmer App
Check out my YouTube Channel for DIY's and other fun stuff HERE
Check out my BMWBLOG!
Originally Posted by Fast Bob
now, go burn your Man Card, and buy yourself a Camry....