I thought I seen a post on here but cant seem to find it on the heater not blowing out full blast threw the vents. when im stopped I get good air coming out the vents but any time driving it does not come out wortha ****. if I turn it to defrost it seems to work just fine, someone I thought said a vaccum line? any ideas?

 

If you have the vacuum operated controls - 2000 and earlier, there's a check valve in the line near the brake booster. If it isn't working properly the vents will change as you accelerate/decelerate.

See the attached picture.

 

just gotta buy a new one?

 

Get a new one.