E46 318i Start problems

Hi. I have one problem with my 318i. Sometimes when i am driving for a long time...let's say hour..and then i stop and park the car and come back after an hour let's say; my car has problems with start. Ok. When i try to turn on the car starter motor turns about 1 maybe 2 times and then the car is running. As i described above..when this happens car starts after 5 or 6 turns. It starts always but it need to turns few more times than normally? Why? This issue doesn't happen often..maybe 3 times a month. I have new spark plugs and fuel filter, service has been done 2000km ago. My rpm needle waves too from 1000 to 850 rpm sometimes..but that's idle control valve. I have cleaned it and it's much better but still sometimes. Could my issue be connected with idle control valve? Thank you for any answers!

Oh yes...no errors found with diagnostic.