Little to no heat at idle

[darbo60]

96 grandam 3.1
Replaced thermostat, water pump about a year old. Heater blows cool to warm when idling, then blows hot when engine rpm is increased. Does this sound like water pump problem not circulating at idle? Any thoughts or suggestions?

[dschild]

Could it be a coolant issue? I had that problem when I was low/empty on coolant.

[Jpit]

I also had the same issue on my 95 Grand Am. It went away after topping off the coolant. Think there was some air in the system.