1997 Ford Thunderbird engine burning rich

i have a 3.8 the intake airflo sensor has been changed and all four oxygen sensors have been changed but it is still running rich and runs rough at idle blowing black smoke from tail exaust pipe. the cooling fan also comes on at cold start like maybe the
fan sensor or something is telling the fan to come on.
if i could wait for my ssi check to get here i would be able to donate but as of now i need a running car so i will have to go for the free question for now..thank you for your help.