The heat in my 94 Ford Ranger stopped working. The blower blows, but the air is cold instead of hot. We've changed the radiator, thermostat, heat sensor unit, heat sender unit, checked operation of heat control(doors work ok), still no heat. Engine does not reach operating temperature-HELP!!
Also, doulble-checked the installation of thermostat-ok

The heat in my 94 Ford Ranger stopped working. The blower blows, but the air is cold instead of hot. We've changed the radiator, thermostat, heat sensor unit, heat sender unit, checked operation of heat control(doors work ok), still no heat. Engine does not reach operating temperature-HELP!!!
Also, doulble-checked the installation of thermostat-ok
You could need a new heater core

I had the same problem with a subaru, and I'm having it now with a 94 ranger. The fix was to park the car on a hill face up the hill when you fill it because the top radiater hose is higher than the filler tube you end up with a big air pocket. It worked on the subaru, I'm in process of replacing the radiator in the ranger but I'm sure that will fix it. Good luck!