I have no heat have flushed heater core and replaced thermostats

Yes flushing your system will clean out your here core is long as you turn the switches on to activate the heater

Regarding this types of problem,i suggest you to go through this help links.Click the link below to go through the procedure and troubleshoot the problem :----

HOW TO REPLACE AN UPPER RADIATOR HOSE

http://schematicsdiagram.blogspot.com/2011/07/how-to-replace-upper-radiator-hose.html

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HOW TO REPLACE A LOWER RADIATOR HOSEhttp://schematicsdiagram.blogspot.com/2011/07/how-to-replace-lower-radiator-hose.html
----------How to Flush Heater Core?http://schematicsdiagram.blogspot.com/2011/12/how-to-flush-heater-core.html
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For heater core replacing procedure. I suggest you to go through this related help links.Its all complete step by step procedure: ----How to replace heater core for All car models?

Click the link below: ---

http://technoanswers.blogspot.com/2011/11/how-to-replace-heater-core-for-all-car.html

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How to Flush Heater Core?

http://schematicsdiagram.blogspot.com/2011/12/how-to-flush-heater-core.html

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How to Remove Heater Core ?

http://howtobyme.blogspot.com/2011/12/how-to-remove-heater-core-on-2008-honda.html
Heater Core Replacement?

http://howtobyme.blogspot.com/2011/12/honda-heater-core-replacement.html

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To replace heater core?http://technoanswers.blogspot.in/2012/02/how-to-replace-heater-core-on.html------

How to replace heater core?http://technoanswers.blogspot.in/2012/02/how-to-replace-heater-core-on_10.html
How to replace heater core on Buick Regal?

http://howtobyme.blogspot.in/2012/02/how-to-replace-heater-core-on-buick.html
----------This will help.Thanks.

Thermostat.? if you haven't? Do it first then try it. While the car is running for a while touch the heater hoses that lead to the firewall. if one is cold and one is hot? You have a blocked Heater core. Follow the hoses back to the engine. Unconnect them both. By using a garden hose flush out the heater core do one side and then reverse by doing the other hose Lots of junk will come out so be care ful. Mistake people make is "Flushing the system" That doesn't mean your flushing the heater core.
Seeing that you have done everything else it could be the thermostat which you didn't list or the heater core being clogged. When you finished installing the thermostat and flushing the heater core out. Replenish the coolant system . If you have a bleeder on the thermostat housing? use it . loosen it and top off the fluid until you see fluid comeout of the bleeder. The system being air bound would cause no heat..

there is two things. one is low coolant the other and most likely is heater core is plugged flushing the coolant causes things to loosen up stuff and it gets stuck in the heater core if you take heater hoses off and back flush the heater core with a garden hose and you will have better heat then you ever had.

try flushing cooling system could be a blocked heater core.if flushing doesnt work remove and replace heatercore.

Hello, No! I'm assuming that the temp gauge is working in truck & you are not over heating. On the passenger side firewall check both hoses going to/from heater core. If both are not warm then it is probably a heating core plug. You will have to replace the heater core.

Sounds like the problem has to be the valve is not opening and thus not allowing the hot coolant to enter the heater coil. Manualy open the valve (engine firewall) and see if heat is present. If this works check your cable from the dash switch as it isn't working the valve properly and needs replacing.

i don't know realy if there is a fuse (though i doubt it) but issues with heatting may be this will help.

If the carpet under the heater core is damp, or if antifreeze vapor or steam is coming through the vents, the heater core is leaking.
Remove it and install a new unit (most radiator shops will not repair a leaking heater core.
If the air coming out of the heater vents isn't hot, the problem could stem from any of the following causes:

• The thermostat is stuck open, previnting the engine coolant from warming enough to carry heat to the heater core. Replace the thermostat.
• There is a blockage in the system, Preventing the flow of coolant through heater core. Feel both heater hoses the firewall. They should be hot.if one of them is cold, there is an obstruction in one of the hoses or in the heater core,or the heater control valve is shut. Detach the hoses and back flush the heater core with a water hose. If the heater core is clear but circulation is impeded, remove the two hoses and flush them out with a water hose.
• If flushing fails to remove the blockage from the heater core, the coremust replaced.
  

the divider door is not opening staying on cool. check the temp. knob out

If u have issues with heatting may be this will help.

1- If the carpet under the heater core is damp, or if antifreeze vapor or steam is coming through the vents, the heater core is leaking.Remove it and install a new unit (most radiator shops will not repair a leaking heater core.

1 - If the air coming out of the heater vents isn't hot, the problem could stem from any of the following causes:

• The thermostat is stuck open, previnting the engine coolant from warming enough to carry heat to the heater core. Replace the thermostat.
• There is a blockage in the system, Preventing the flow of coolant through heater core. Feel both heater hoses the firewall. They should be hot.if one of them is cold, there is an obstruction in one of the hoses or in the heater core,or the heater control valve is shut. Detach the hoses and back flush the heater core with a water hose. If the heater core is clear but circulation is impeded, remove the two hoses and flush them out with a water hose.
• If flushing fails to remove the blockage from the heater core, the coremust replaced.