1998 volvo v 70car starts great then when warmed up stalls and , it starts good again also cant seem to turn off teh heater "fan"

The car stalling when warmed up is most likely a fuel pump. If the vehicle is not awd then the pump acces is from the trunk. Pull back the carpeting and youll see a circular plate with wires coming out of it with some nuts holding it down. Remove plate and theres your pump. Remember to index your pump, take a grease marker and mark where the tubes coming from the assembly are pointing, if it isnt indexed correctly, your fuel gauge wont read properly. The heater fan issue could be a couple of things, do you have ecc? Like can you move a knob to a set temperature and move another knob to the auto setting? If so its probably the fan power unit. If you have manual climate control then it is probably the switch. Hope this helps.