Automatic Climate Control Problem

[04MRADR]

:cool: Got a starnge problem which I need help figuring out. Actually its two problems but I'm thining they might be related. I noticed this past winter that my heater part of the Automatic Climate Control worked fine but when I came to a stop at an intersection the heater started blowing cool, not cold, air. When I hit the gas the heat came on again. My mechanic thinks it might be the heather control valve is a bit clogged. The second problem is when I go to hit the gas with the air conditioning part of the climate control on it suddenly blows out the defrost vents in the top of the dash and the floor. If I let up on the gas it starts blowing out from the vents in the dash again in most cases. Sometimes when I let the foot off the gas it doesn't come out the vents and continues through the defrost ducts and floor. If I shut the Automatic Climate Control off for a few minutes it works again okay. Do I have two separate problems or are both related and what could be causeing this?

[B.C. Bake]

Did you check air in the system. "water system" And did you make sure there were no vaccum leaks?

[vegasmarauder]

Air flow from defrost and floor heater ducts at the same time without being selected on the control head is usually a large vacuum leak in the system. Again, almost always it's the seals in the electronic control head (dash control). Its about a $400.00 part over the counter at Ford I think. I have seen a few posts about changing the rubber seals inside the control head, but have not tried that. Out here in the desert they seem to fail after a few years.

The no heat may be the low coolant, or the blend door electronic controler. This blend door controler is directed by the electronic control head. Both problems may have the same cause.

[EbonyMarauder03]

Do a search for the "O" ring replacement post. I work at a Ford dealer and was able to recover my old one when the warranty went through. I installed new "O" rings and could tell some of them weren't sealing. I had the same problem with air coming out of vents that weren't commanded for. There a 4 "O" rings to replace. It just takes a little bit of time and finess.