I have a 93 grand am 3.3l.I have a bit of heat for about a minute or so after I turn on the fan.I was told that the heater core may be plugged or restricted. Is this correct info or is there another problem
First warm up the car and turn on the heat.
Then touch the 2 hoses going through the firewall to the heater core.
If one is hot and the other is not.
You have a clogged heater core.
Also check your fluid level.