No matter where I set the heater selector I only get heat from the defrost until at least 1/4 throttle. At highway speed with the selector set to floor or vent it workes fine. As soon as I let of the throttle it goes back to defrost. I'm guessing I hooked a vacuum line up wrong during an engine swap, but I'm not sure where it's at or where it should be hooked up to get the correct vacuum all the time.
On the passenger side of the firewall there is a vacuum hose that goes to the blend door. That will cause it to only work in defrost.
It's in the engine bay side not under the dash.
I don't have time to check it out right now.(gotta go to work), but when I find it , where should it be hooked up so it get's vacuum at idle? I'm figuring it's only getting enough vacuum at 1/2- W.O.T.
its a three way round looing do hicky. one line goes to the vac tree, the other goes to ,, a thing a ma jig inside the fender that looks like a cool ass black plasitic ball,,, the other goes into the dash to your hvac.
Thank you. I need to look at that tomorrow. My feet are still cold from the ride home from work.