no heat

Hey gang, I am new here and I have a question. I have a 97 malibu v-6, 3.1. The heat in the car only works when the engine is reving. Does anyone have an idea how to fix this problem?

If the fan itself works but the air just doesnt get warm when the engine temperature reaches normal operating ranges then check that your heater core isn't clogged or bypassed. Also, check that the themostat is good. It could be that it isn't popping and therefore the heater core isn't being included in the flow path. Beyond that, either hope that someone else here knows more specifics (which is likely since I'm no expert) or have your mechanic take a look at it. Good luck!