My 99 Dakota SLT has a heater problem. It just doesnt get warm enough in cold weahter. It worked fine for years but last couple just dont seem to blow hot air anymore. I replaced internal thermostat myself and still no warm air. Any ideas welcome ! Thanks

 

Plugged heater core???

 

Sounds likely that it is at least partially clogged. You can try backflushing it. Take the hoses off of the heater core and flush it out good with a hose. It might help.

When was the coolant flushed last?