No heat from heater?

Check the heater core if its clogged-up

Before working on it, start the engine, allow the engine to warm up to operating temp with the heater on, and feel both heater core hoses. If both are hot, the core isn't plugged. If only one gets hot, then it is.

Hello -

To better assist you can you tell me the size or your engine in liter and the 8th digit of your VIN.

Okay. . .. . .. . .do me a favor. . .. . .. . .. . ..once the truck is at operating temperature check the heater hoses going into the firewall. . .. . .. . ..are they both hot. . .. . ..the same temp or is one hot and the other cold.

Next some of the common conditions for insufficient heating are as follows:

1. A leak in the cooling system.
2. A low coolant level.
3. A loose or worn drive belt.
4. A leaking or kinked heater hose.
5. A cracked or missing radiator cap seal.
6. A stuck thermostat
7. Temperature valve position

As for the windshield fogging. . .. . .. . ..on the pic below. . .. . .. . .many times our windshield fogs because we don't have outside air coming in. . .. . ..therefore the inside air that is being blown (or not) fogs the windows. . .. . .. . .there has to be air circulating. . .. . .. . ..

Depending on the outside temp and the inside of your car. . .. . ...lets say it is raining outside and hot. . .. . .. . ..you turn your AC on and the windows fog. . .. . .. . ..make sure it isn't on MAX A/C, number 3 arrow as your vent is closed off and you are not getting any outside air. You need to have it on number 4, 5, 6, 7, 8. Then your temp control number 2 is on full cold.

If it is a little cool out or cold I guess make sure you have the temp control on whatever you need but the selector needs to be on again, 4,5,6,7,8. I say 4 because you will still get warm air though this selection still pulls outside air in. . .. . .. . ..

Try the above and let me know. . .. . .. . .. . ...

For the heat. . .. . .. . .please check to make sure your coolant is full. . .. . .. . .replace the radiator cap, make sure your belt is properly tight and check the hoses as I asked and let me know.

First I would like you to feel the heater core hoses and let me know if one is hot, neither are hot, both are hot, or if one is significantly cooler then the other, check directly by the firewall.

Sounds to me that your blend door is functioning properly.

Check the thermostat and heater core if its clogged-up if okay could be an air mix/blend/mode door problem, vacuum and actuator and HVAC control module.