intermitant fault in v reg 2000 328i driving my father in law nuts!!!

[pepperami]

hi,any one help,my father in law has a bmw 328 and recently it has started playing up.when the car is warm after 10 mins or so if he turns engine off it will have trouble starting,also when he slows down at a junction or roundabout when he goes to pull away it will hesitate and is not responsive.also sometimes a t a junction or wotever the car has been known to stall,any ideas comments would be really usefull.he has had it plugged in for diagnostics and the couldnt find a fault!!ahhh