Little or no heat, have flushed system, replaced thermostat. on 2002 Ford F-150

i removed heater hoses and can flush water through core in both directions. Fan works but blows cold or barely warm water. any ideas what problem may be. oh yea core is not leaking or fogging window.

by in Jackson, GA on December 04, 2012
4 answers 4 comments
ANSWER by on December 04, 2012
when you turn the knob,or move the lever to change from hot to cold or vice versa,do you here any noise from under the dash? this truck has blend doors which control the temp of air that you get.they are controlled by small electric motors called actuators. in is very common for those to fail on your particuliar year and make.
COMMENT by on December 07, 2012
Thanks I will llisten to see if i can hear operating.
ANSWER by on December 04, 2012
Check heater control valve for proper operation. That black thing in the heater hose near firewall with the vacuum hose hooked to it.
COMMENT by on December 07, 2012
I will look and verify vacuum line hasn't been disconnected. What is best way to insure that it is working properly?
COMMENT by on December 07, 2012
Toward the bottom of the valve is a lever you can see if it changes when switch temp. control. If it doesn't move it can be moved by hand manually to see if heat works then. A helper is handy!
ANSWER by on December 05, 2012
agree with both posts 1 and 2
ANSWER by on December 19, 2014
yes I did aii these things and stii no heat
COMMENT by on December 19, 2014
do you hear any clicking under the dash? you never said.when you change the controller from hot to cold do you hear any movement under the dash? is there any temp change at all?