heater in 1990 infiniti q45 not working????

[blondi]

i bought a 1990 infiniti q45 a year ago. i had a used motor put in and it runs okay but not the way i feel it should be. the motor runs loud. so i am sceptical about the ccar. anyways. my heater on the 2 vents on the dash by the door if you put your hand by them you can feel warm air so i dont think the heater core is bad. but the heater will not blow the air and is not defrosting or heating up the car. what coudl be the problem

[dan b]

I just took my heater fan motor out and blew it out with compressed air and wala it runs at full speed just like new it was full dirt. it took me 2 hours start to finish