[jdbarman]

I have a '98 Ford Windstar that only allows air out of the defrost vents. I have checked the vacuum lines that run to the main heater control and rear heater control on the console and did not feel any suction on the lines. I am assuming this means there is a leak in the main black line that feeds both of the controls. If this assumption is correct, what is the best way to find and repair the leak? If this assumption is likely incorrect, what are some other problems to check for?

[opsuper3]

After about 50 views, no replies. Not trying to be rude, but try searching for the terms. Poppy does a whiz bang job of walking you through the steps to troubleshoot and repair the beast.

[Poppy]

thanks opsuper3

Please check this thread.
In particular the first four posts, and the link that I posted in there too.

I had seen a thread on another site that went on and on about the green slime that Canuck623 is referring to in his post.

98 Windstar A/C door problem

BTW... you are on the right track... vacuum leak causes it to default to defrost.