1999 Taurus Heat Problem

When I turn the knob over to heat, I can hear a thumping noise. I tracked it down to behind the dash board. There is a blue, 5 wire plug that when unplugged stops the noise. I'm guessing there is a door in there? How do I take this thing apart to get to it?

Is the plug on a small white plastic thing aboue 3 by 4 inches? If it is, that is the blend door actuator. There are 4 little bolts that hold it in place. Fairly easy to change once you figure out the right angles and size extensions or no extensions to use.

Is the plug on a small white plastic thing aboue 3 by 4 inches? If it is, that is the blend door actuator. There are 4 little bolts that hold it in place. Fairly easy to change once you figure out the right angles and size extensions or no extensions to use.

It's a small blue plug, maybe 1" x 1". It's located about midline and right behind the lower mounting bracket for the glove box. It is right next to a larger white plug with strange wires and a strange connection, maybe some vacuum hoses?

Does the plug go into something that looks like this?

http://usera.imagecave.com/way2old/blenddooract.gif

If it does, that is the blend door actuator.

It's about 12" to the right of that. That piece is right behind the ash tray correct?

OK. It is behind the ash tray. I will look again tomorrow and see what I can find.

I'm at loss then. I thought for sure it was the mixer door. If I move the temp gauge about 1/2" from cold it starts that thumping noise.

I took the ash tray out and followed the wires back from the blue plug and they plug into the blend door actuator as you have pictured. I pulled the actuator off and can manually move the door from hot to cold. Is it safe to assume the actuator is bad? I watched the pin on it move and it is really slow. Is it just not strong enough to move the door anymore?

Any idea what a new one costs?

Our cost on blend door actuator is around 32$. We are a government facility and get a break on pricing. Yours will be a little higher. If you have the blend door off, it pries open easily. Look at the little plastic gears to see if any are sheared off causing the problem.