Dodge: No Heat, heater control valve, heater cores

Question
I have a 1996 Dodge Dakota with 51,000 miles. My heat is luke warm.I have had the thermostat changed,radiator flushed and filled.Is there a heater control valve causing this,or is it possible the heater core is plugged.I would certainly appreciate any suggestions.

Answer
Larry,
If you've changed the thermostat it's probably the heater core.Have you tried back flushing the heater core?Have you tried touching the heater hose to the heater core when the engine is hot?I've read about a lot of people having trouble with the heater cores being clogged,i would try doing a back flush first it's a lot easier and cheaper.