heater not blowing hot air

Ok here is the low down of what has happened. I bought new spark plug wires and in the process of replacing them I had to move to heater hoses around a little bit to get the wires situated. After i got all the wires replaced and i took it for a test drive i noticed the heater wasnt working now. so i go under the hood and checked both hoses (inlet and outlet) and the outlet hose was not near as hot as the inlet. so i pulled both hoses off and what i found inside is kind of disturbing the inside of the hoses were lined with some sort of hard crusty stuff about 1/16" thick, dark brown outer layer and yellow inner layer. My guess is that my dad (previous owner) tried to stop a leak with that leak stop stuff. Anyways I guess what happened is when I was moving the hoses around the crusty stuff crumbled and possibly clogged up the heater core. So the first thing i did was hooked up a water hose to the "Outlet" side with the heater on to see if i could backwash that crust out of there, and water came out the inlet side without a problem. Then I flushed the entire system to get any remaining junk out and replaced both hoses. So does this mean that the heater core is not clogged even though the outlet hose is still cooler than the inlet hose? When I turn the heater on all the way to 90 degrees it still blowing cold air and I can hear the compressor kicking on and off.

My compressor does the same thing but now maybe u might have to get the system profeshionally flushed. Hope this helps.

Bill

actually what i ended up doing is this...... there is a vacuum valve that is located in front of the engine that is controlled by a vacuum hose. it took me a while to figure this out but a little investigation led me to find that crazy little valve thinggy. i forget what they called it but anyways i just took that valve off and bypassed it to make it constanly flow through my heater core and when the summer comes back around and i dont need my heater any more i have installed a manual valve that i can turn by my hand and close off the flow through the heater or just leave it a lil cracked open so when i need to use my deforst it will be avaliable. that was my grand ol' fix

Can you please tell me where in the front of the engine that vacuum valve is located. I have a 4.0 and am having the same problem. Thanx.

if you follow the heater hose coming from the firewall you will first come to a metal connector that is attached to the engine and the it will turn back into the rubber hose and then the heater core vacuum valve. If in not mistaken I had to take the fan and fan shroud off to get to it because its tucked under the thermostat housing area. Make sure once you take it off and bipass it directly that you take a screw or something of that nature and plug or cap off the vacuum line. If you still cant find it let me know and ill go out and take a couple pictures of where its at.

My Heater is blowing but no hot air ever since i used the /ac this summer any answers ??