heat issue

Hi all, I have a 98 expedition, 58000mi, with multi zone heat. Problem is:
At stand still idle, heat blows warm to hot.
While accelerating, heat blows hotter,
While at idle and in motion (foot off gas) it blows cool.

It has new anti freeze, thermostat and cap. Registers 14 psi at cap.

Thoughts? All this has been done at ford dealer, I just bought it and it is warranty work. They are stumped.

Thanks-Jeff

Hi all, I have a 98 expedition, 58000mi, with multi zone heat. Problem is:
At stand still idle, heat blows warm to hot.
While accelerating, heat blows hotter,
While at idle and in motion (foot off gas) it blows cool.

It has new anti freeze, thermostat and cap. Registers 14 psi at cap.

Thoughts? All this has been done at ford dealer, I just bought it and it is warranty work. They are stumped.

Thanks-Jeff
Hey jeff, have you found out anything? I have the same exact problem, and I also have tried a new thermostat, flushing the cooling system, and with no success. My Exped, is a 97 and has been doing exactly the same as yours, would appreciate any info, you could give, thanks bc

hmm, only thing that comes to mind is air in the system..

Bingo, thats what it was. Thanks]

good deal!