My heater wont blow air when i switch it to the floor position on the knob, all the air comes out the top of the dash, it wont switch to the vent, floor, etc. Has anyone else ever had this problem, if so, how can i fix this? please help, its cold as hell outside.
The default is the defroster mode. It sounds like your vacuum signal is getting disrupted. Look under the pass side of the dash for any broken or loose vacuum lines.
I have had the same problem since I bought my stang and have been looking for a solution. Too bad that now I know where to look to fix it. I have it under a tarp which is covered with snow.
The knob works from cold to hot, the vaccum lines are good under that dash, maybe a relay switch? If so, where is it located? BTW I am missing the vaccum line that connects to the EGR valve, i dont know if that has anything to do with the heater problem....
Ok so you are getting hold and cold but you are only getting air coming out from the vents?
Look by your A/C accumulator, it is on the passenger side firewall. There should be a few lil vaccum lines there. The ones coming out from the firewall is what controls the air being let into the other vents. If that is not plugged in it will give you the problem you are having.
Also under the passenger side of the dash there is a small canister with a yellow vac line at the top. Make sure that is connected.
Have you had you dash out? Or your heater core replaced recently? I agree with these guys, it sounds like a vacuum line. I would say the tiny black one or the yellow one. I usually find its the yellow one. Goodluck.