Need Blend Door Procedure-98 F-150 5.4

[hoganlo]

Does anyone know where I can find the blend door procedure for a 1998 F-150 5.4? I seem to have the issue where it blows cold, temp control knob has no effect but if I hid a road bump hard enough I luck out and start getting heat.

I just don't know the proper process to get to and remove and exactly what I'm looking for. Any help would be appreciated!!

This site has saved me a ton!!!

Steve

[hoganlo]

Okay...after reading other posts I've taken off the plastic over the tranny hump and pulled out the plastic that directs the air flow. I have removed the little white box...not sure what this is actually called (actuator/blend door motor?). Anyway, I turn the temp knob and the shaft turns just fine on that motor...the white shaft fits into a black hole/tube and I can actually turn the tube, but the temperature does not change.

What next? I assume that there is a door that rotates when the shaft and tube turn, but I don't see it or how I get to it at all.

Any help would be appreciated!!

[sheetsd66]

I did a google search for 1999 F150 blend door and started clicking on links. I can't remember the exact site, but I found a forum similar to this one with excellent pictures. I just replaced mine about a month ago, give yourself plenty of time. Its an all day job. You may want to double check the operation of the door itself; you said that when you turn the tube the temperature doesn't change... it should. Make sure you turn it all the way through its range of travel. You should feel at least a slight temperature change thru the vents.

[yekratsb]

Originally Posted by hoganlo

Okay...after reading other posts I've taken off the plastic over the tranny hump and pulled out the plastic that directs the air flow. I have removed the little white box...not sure what this is actually called (actuator/blend door motor?). Anyway, I turn the temp knob and the shaft turns just fine on that motor...the white shaft fits into a black hole/tube and I can actually turn the tube, but the temperature does not change.

What next? I assume that there is a door that rotates when the shaft and tube turn, but I don't see it or how I get to it at all.

Any help would be appreciated!!

How in the world did you get the plastic out that directs the air flow? I'm trying to pull out the actuator without removing the black ducts below it but I can't seem to push it down far enough to pull the white shaft out. Does the shaft disengage from the actuator?

[hoganlo]

I used an angled screwdriver. I have the lower section taken out and still have not completed the job! Been driving around half torn apart for over a month!! When I accelerate, the door flops over to heat so I turn the air off...I've gotta get this thing foxed, but haven't had any time.

[sheetsd66]

You gotta pull the dash to get at the blend door. You can get the replacement door from NAPA ($12) or the dealership ($40).
Blend door replacement with pictures - F150online Forums

[hoganlo]

Thanks sheets! Hopefully I can tear into this soon!!