high guys well i took my car by the shop twice frist time the fixed the heater swicth so the air will blow out the vents or defroster, but i still had no heat, so again yesterday they said they thought it was the heater core, so i took it home and replaced it still not blowing heat, anyone got any suggestions , thanks

 

Heater control valve...

Follow the heater hoses to the valve, check to see if it has vacuum when it should; if it does, replace it; if it doesn't, investigate all the vacuum lines leading to it, starting at that vacuum switch.

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"So many Mustangs, so little time..."

 

Also did you check your thermostat?

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One more thing, it may divert air to the vents, but does it also divert air over the heater core? My digital das car, had a little motor that moved the door, the connector from the door to the push rod was broken, whci had the thing stuck in cold air mode.
Corry

 

thanks guys for the help, well i changed my thermostat a few months ago, so i know thats not it i hope lol, allso when i put in the heater core i have the same deal with the motorized door, that is working, i had the dash out and held my hand next to the heater core while the car was hot and nothing, so i went to see if the lines going in where hot, well no they are just warm form the engine, now the frist post, the heater value is that in the little plastic tube looking thing,with the one vacum line going into it, and three hoses comming out one to the throttle body, one that goes into the block and one that comes from heater core, i pulled of the vacum line and its not sucking, so im guessing that line is broke or is not supossed to have suction ?, i went by the auto parts store today and ask to see a heater vaule for my car and the guy brought back a metal tube with two ends on it in a sorta t shape with a litte turn on vaule , does that go or is that in that little black box ,im kinda confussed, if nothing else cant i do away with the whole heater vaule and hook up direct so water runs through the heater core at all times, ?????? HELP LOL

 

ok read frist post again VACUM SWITCH where is that located, the vacum tube from the heater vaule does not have any suction, so when you follow that little plastic tube back it goes into a engine harness down into the firewall but i am getting suction from other places such as cruise controll and all , ???????????/

 

ahhhhh....the fun you could have with a vaccume diagram and some tech manuals,sorry,I'm just being a **** because I really don't know.

 

I am not sure where the vac line is supposed to com from. Mine too gets no vacume, and I replaced the console switches, and the heater core, and the heater control valve. Since I never use my cruise control, I found a line w/ vac all the time, and split a line out from that to my heater core. As for can you eliminate the heater control valve, the answer is YES! In fact, they never used to have heater control valves, so you can just directly run the coolant lines. Unless someone here can tell us why we get no vacume to our heater coltrol valves
Corry

 

im having a similar problem with my heater. mine gives out heat but wont switch speeds. it always stays on the low speed. Have u checked your fan motor? thats what my problem is, and as soon as i play with it for a while im sure ill will fix it.

 

Jeremy,

take a vaccum line with suction and plug it into your valve. See if this makes a diference. You can also take the valve off and check it for operation using another cars vaccum or a vaccum pump.

Lastly, you can by pass the valve temporarly as well.

William.

 

SWEET guys, thanks for the info, yeah today im going to try to split a line off my cruise controll and if that doesnt work then im just going to bypass the heater vaulve thanks guys, man i love this board

 

well im back guys, guess what still no freaking heat, tried everything as everyone said in the above post, i did away with my heater core and hooked up direct, well no heat, last possibly solution, something stuck in the lines,well today, ran a water hose through the lines, and through the whole clycle through the oil cooler and all, (89 350 l98) anyways, water was going through fine and gushing out the radiator cap, so im stuck anyone got anymore ideas, this whole thing doesnt make since, i can hold my hand next to the heater core while the motor is hot, and still not one bit of heat ????????????????? , everything is hooked up right, had three engine macanichs look at it, they dont know either, ????

 

Exactly where (and I do mean exactly) are your heater hoses hooked to on the end of them opposite the heater core?

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"So many Mustangs, so little time..."