I have a 94 Olds w/3.1 with a circulation problem. Engine will get to 200 degrees but heat in cabin is not great unless you increase rpms. Replaced thermostat today but not satisfied with heat. Could a water pump be bad without leaking?

 

Your problem is not with the water pump. If the pump was bad it would overheat.You have a blockage in the system, most likely in the heater core. Remove the 2 heater hoses from the engine then pour a small bottle of peroxide in and let it soak for about 1 hour. Then take the garden hose and squirt through the core. Reassemble run the car till the air pocket burps ( when cooling fan cycles your good) and see what happens.