I just had this issue on my 03' X5 with 228,000kms. I removed the idle control valve and cleaned it with intake cleaner, it ran good for a bit then i noticed the idle would be a bit high. Same thing, truck would stall from a standing start or going reverse, basically when the truck would first have a bit of load on it. Restarting is no poblem, touch the gas, stalls again, no codes. Finally it threw a code, P0340, generic for cam position sensor bank A. After some research that code is for the intake cam position sensor. Cleared the code truck runs incredible, better gas milage. I forgot to mention that when i was first having the idle problems i did get the code for idle control valve, can`t remember what it was, that`s why i started with cleaning that first. Changing the intake cam position sensor isn`t that hard, the exhaust is even easier. The intake sensor is located under the vanos solenoid. WOrd of warning thou, do no tuse after market sensors, your truck will have issues. The sensor cost $175.00+$4.00 o-ring, which you have to replace as well. Hope this helps