Greetings all

Seems my 2001 developed a weird problem. The Blendoor side of the controls appear to be stuck on Def/Floor BUT if put on Panel/Floor there is a few minute hesitation then the unit will switch over from Def/Floor to Panel/Floor for a minute then switches back again.

If I put the controls to Panel only it works fine. If I switch from Panel to Panel/Floor, then it works for about a minute before switching back to Def/Floor.

Did I lose anyone yet?

I replaced the Heater core about a year ago. This all just started within the last month or so. Any ideas?

Thanks..

 

Did you replace the Bendoor at the same time you did the heater core? It could be split on the bottom. Just a thought.
Also the entire air flow operation is controlled by small plastic tubes carrying vacuum. If you have a leak it will shift the air door back and forth as the manifold vacuum changes. Start looking under the hood at the firewall by the battery for broken or cracked hoses. Also look behind the controls under the dash. All the tubes are red, white or blue.

 

Thanks for the reply.
Bendoor looked fine when I did the core.
I will check on these hoses. I could have done something under the hood as I was messing around with the wheel well and vac hoses during the summer....