i have a 1994 pontiac bonneville, i turned the heat on and nothing happened. i replaced the blower motor, which it now blows out air,but only cold air. any thoughts on what my problem may be.

https://www.google.com/#q=1994+pontiac+bonneville+radiator

pressure test the system to look for any other surprises~

hopefully, A) no one has 'Panic' filled with hose water after an overheat..B.) the coolant is much more than two years old creating a sludge of boulders and muck C.) your thermostat is probably mucked in the open position~ ....so in conclusion, get the cooling jacket flushed free of debris and rust...you know it does not take much to corrode an aluminum head~ Yours is the opposite problem with gummed open t-stat~...btw, you did replace the t-stat and get the coolant changed? NO?

you can see the testament of a prior overheat by stains underhood~

so yes...a CRACK, loss of pressure and coolant flow could give you NO HEAT~....a thermostat that is jammed open would be the first cause tho~

a crack, no! coolant still going around, heater hoses hot? if yes two are then inside diverter not diverting, one hot ,no coolant moving threw heat core , maybe plugged with goop from trying to fix crack with goop