, i replaced my heater core, and after replacing the whole dash, i realized the blend door was stuck on heat. so i replaced the blend door motor and it still is stuck on heat. so i then repaced the switch and STILL NO blend door action.. i'm stuck now. i figured it was one or the other.. any other problems or thought similiar to mine?

 

Vacuum leak...check the ends of the hoses..might be cracked. Otherwise leak could be anywhere.

And new motor/switch could be defective...wouldn't be the first time this happened.

 

well, i guess that system needed time to recognize the new part?? cause i woke up this morning and everything is working properly.. the heater core is pushing out heat and the blend door is doing its thing correctly... so this is a happy ending.. thanks for the post.. i do know that i have a vaccuum leak in the system. during acceleration i loose the air flow to the defrost. i'm still trying to track down this problom...