Heater problems

[Perez56ma]

Whats up errbody. Just bought my 02 4.7 Im new to the forum. So my heater is not working. Every time i turn it on it blows cold air. What could it be?

 

[SYKRAMMAN]

Whats up errbody. Just bought my 02 4.7 Im new to the forum. So my heater is not working. Every time i turn it on it blows cold air. What could it be?

If it’s not over heating then I’m gonna bet it’s your blend/mode door/s, use a flashlight and look up under dash in between glovebox and hvac box to see if your doors are functional, very very common problem with these trucks.

And welcome to the forum, some great people in here and even better information.

 

[Wahrsuul]

Could be the blend door as SYK said, but also the heater core could be plugged. I had to back flush it on my 01 to get it to work.

 

[Perez56ma]

SYKRAMMAN Wahrsuul. Thanks guys! I will definitely take a look at this. I need to get this fixed bfore it get colder!!

 

[Jason G Slabaugh]

Thermostat could be an issue as well, cheap insurance to change it out