no matter what setting i put the selector on the vent only blows out the front. i get a little out of the floor and defrost. what is the cause of this? i did replace the TC vacuum switch, there was no fluid dripping out of the vacuum line when i pulled it off.

 

check for vac under the hood. If none u will need to pull dash panel off and remove heater control panel. There is a connector with(if I remember correctly) 6 hoses. Unhook it. 1 should have vacuum. If doesn't there is ur problem. If does then remove the glove box to see if the actuators are moving.
If they do move then problem a flapper broke inside duct work that is broke.
There is a rubber disk inside selector switch with a bunch of grooves that can wear down enough to cause a vacuum leak.

 

how do i check for vacuum under the hood? there are so many vacuum lines what do i look for?

 

Air flow is routed by vacuum controlled actuators; there is likely a leak. Find the vacuum lines at the left corner of the engine bay and check all the connections and lines. There is one line that goes through the firewall to the HVAC control panel.

Going to take a bit of looking around but this should be an easy fix.

 

Start in the middle at the selector switch. Unplug connector and start engine. If there is vacuum then ur problem is in the dash. If there isn't the problem is between the connector and the engine. Finding a vac leak can easy and hard. Just look for broke or dry rotted area and sometimes u can hear them.

 

UPDATE: i got the problem solved, on the driver side there was a vacuum line going into something mounted on the intake. the line was sucked in and had a split in it. i removed it and cut it back, and hooked it back in. and now i am able to select between floor, vent, and defrost.

 

Best to replace the entire line all the way to the check valve, (near the brake booster). It should say, on the side of the line, what diameter it is. Good idea to check all of the lines, if they are squishy, cracked, or turn your fingers black when you mess with it, replace it.

 

i will be sure to do that as my hands were black after doing this. also had some cracks, but for now its working again