Hi all I carpool and I drive a 95-F-250 and my buddy drives a 2002 F-150 both 4x4.Its cold here in Maine. When we left work his heater was not working. Its a 45 min trip. Both hoses are warm. The heat worked on the way in. The fan blows great, just cold air. we switched from hot to cold and back to hot and had heat for about 2 seconds.All the power and fuses look ok. The thermostat is 195. It looked by the guage to open and close and never came close to over heating. Everything looked normal. Where to look next,any Ideas? thanks Bob

 

Try replacing the actuator. It's an electric motor that open and closes the doors/flaps.

 

Thanks , I'll give it a shot. Bob

 

Watch for pieces of broken plastic at the actuator post going into the case. If you see that your blend door is broken.

 

You might even block 1/4 of the radiator front space with some flat cardboard, ect. In very cold weather, this simple procedure will help the engine warm up faster, better heat, and give the engine plenty of cooling when you are driving. Just a tip, my Dad does it all the time, and has heat nearly immediately on his Hemi Ram. Plus the temp guage runs in the normal range in temps 30 degrees and lower, outside (NE Ohio)

 

My 2004 F150 Supercrew has developed a heater problem within the last week or so. It will heat occasionally but more often not.