ok here is my problem i got a 81 ford f150 with a 302 and when i turn my heater on it dont come out of the vents it comes out in the floorboard and the defroster holes.and it does the same thing with my AC. what can i do to fix this ? thanx

 

The default setting is for the defrost vents. Coming out of the floor vent is a little different but it sounds like you have a vacuum leak or bad diverter. Check the vacuum line going to the diverter under the dash to make sure it is connected and not leaking. Also, if the line is OK check the diverter diaphragm to see if it is leaking or the diverter is binding or sticking.

john

 

is the diverter on the drivers side/passenger side/ in the middle? what does it look like?

 

The diverter should be located around or in the blower plenum on the passenger side under the dash. There should be a vacuum diaphragm on a servo with a rod that is mounted outside the plenum with a rod going into the plenum. If you locate the blower motor either from the engine side on the passenger firewal or by looking under the dash you should see what looks like an airbox. That's the plenum.

John

 

thanks alot
ill take a look tommorow