I have no control over flow of heater/AC air distribution. I understand this is a common problem in the old rangers. Some valuce shaft must be broken. The motor that controls the flapper valve moves. Any ideas.
Lyle

 

If your air comes out of the defroster its vacuum leak. If you have no control over temperature then its the blend door.

Dash is the same from 95 to a new truck on the lot. Not sure what an older ranger means to you.

 

I have no control over the temperature so as I suspected its the blend door. Its a 1999 ranger.

 

option 1 is to pull the dash and replace the heater box.

option 2 is cheaper maybe easier.
Free Ford Blend Door Fix

 

Here's another approach - replacing the blend door without pulling the dash. I haven't tried this myself but it looks promising.
Quick and Easy Blend Door Replacement Tutorial

 

Thanks, I'll give option 2 a try.

 

Yes, that can be the cheapest/easiest and it often works. If not, then it's blend door replacement time.

 

how do u fix it if it was a vacuum leak? my blows out defrost after a certain rpm or a certain vacum is pulled while accelerating. but once ive stoped it goes back to where ever the control is set to. how do i fix it?

sorry to jack an old thread i was doing a search and found this thread

 

Sounds like you have an issue with the vacuum reservoir. Its in the passenger side front wheel well. Probably has a small hole in it.

To chase a leak you will need a hand held vacuum pump and follow the lines testing each one.

 

96 Ranger heater temp issue - when the truck is moving the heat works good ( temp contol on hot ), when i am at a stoplight for longer than a minute the air from the vents starts getting cool until the truck starts moving again when the vent air starts blowing hot again. If idling first thing in the morning ( for at least 10 minutes ) the vent air is cool until i start driving down the road when the vent air gets hot like normal. I already replaced the "heater valve box " inline with the heater core hoses. (the heater temp is of course at the HOT setting always) . Any ideas ?

 

If you are stopped and rev the engine does the heat come back?

This is a different issue then the blend door.