heater help

[fivespeedsteed]

so my heat has gotten to not be as warm as it used to be. car is in the same temp. spot on the gauge. isnt doing the misting thing like the heatercore is gone. my friend (94gtho) said he replaced the heater hoses in the engine bay or something and that helped his. my other friend said the vent could be stuck, so turn it from cold to hot, cold to hot, cold to hot, and see if th at helps. didnt. so what can i replce that wont be the heatercore?

also in the mornings when i go out to my car to start it before i drive, i star it and let it sit running for 10 minutes or so, is it better to turn it on and leave the heat off so it can warm up or just turn it and the heat on. i know the heater can keep your car cool and make your temp go down so i feel like it wont get up to temp if the heat is always on.

thanks for the help.

 

[Darkwriter77]

Could be a vacuum leak somewhere behind the dash, and the blend door is not closing all the way in one direction or the other. Just have to poke around there behind the glove box with the car running and listen for hissing. Unplug vacuum lines back there one at a time, see if anything changes; see if the temp changes with the line only pulled, and then plug the line with your finger and see if that affects it. You might have to go as far as pulling out the HVAC control deck to see if something has come loose or split or something from one of the vacuum lines back there.

I'm not sure if Foxes have the same setup as Panthers, but on Crown Vics they tend to default to a full-heat setting when there's a vacuum leak. Be thankful that Fox Mustangs don't have that stupid, STUPID Electronic Automatic Temperature Control (EATC) system, like what I've got on my Town Car. Both of my hands look like a rabid tomcat got hold of me from all the scratches and missing chunks of skin I obtained from trying to remove that STUPID heater blend door actuator - basically, some dimwit at Ford thought it would be "cool" to use an electronic servo (motor) to open/close the heater door, instead of a reliable and simple vacuum actuator. Instead of replacing the actuator, I just manually moved the blend door lever to full heat and wedged it there; come Springtime, I'll just reach in behind the glove box, move it back to the cool position, and wedge it into place for another nine months.

If it turns out to be a vacuum line issue on yours, just get some hard plastic line from Autozone or wherever for a few bucks and splice it in; if it's the vacuum actuator, maybe check out 50resto.com or the boneyards and pick up a good one, probably less than $30.