I have a 2008 Ranger and this morning the heater would not heat. What could be the problem? Thanks

 

Probably a bad thermostat .

 

Check your coolant level.

 

change the thermostat ,this regulates the heat .

 

i have an 08 ranger sport and have this same exact problem.
i changed the thermostat and it did nothing.

 

I am not sure if its on the ranger . But there is a valve in the heater hose on the passenger side .check this . it could be stuck shut or your heater core (behind glove box ) could
be plugged . It aint hard to trace down . Good luck

 

Running your heater this time of the year in the state of Texas is a problem. If your cold roll the windows down.

Edgewood, TX weather report

Currently Partly Cloudy 92F
High 97F
Low 70F

 

ok first grab both heater hoses and feel for pulse and warmth.....you wont get burned but wait for water to heat and thermo to open...if you feel water and heat..then your heater CORE is plugged up or bad...very easy fix....if you do not feel water pressure and warmth, then remove therm and look for crap in the housing......if thermo is NOT opening, then NO water is getting to heater core thus no heat....good luck
jim

 

I'd bet 100% that it's your electronic blend door actuator. Mine failed a few weeks ago. Try using your AC...and then start turning the temp to "hot" and see if the AC gets warmer - My AC would stay locked in on the coldest temp when the actuator failed. I tested mine by removing the old actuator, with wiring still plugged in, and moved the temp **** on the dash, but the actuator never moved. Plugged wiring into a known good actuator to confirm failure of part - I replaced with a blend door acuator from NAPA. BTW, the back screw is a pain to remove/install.