I recently determined that the blend down accelerator, on the passenger side, was making a thumping sound. I could stop the noise by unplugging it,then my heat wouldn't work. After taking it apart and cleaning grease from the contacts, it seemed to work. This is my problem now, The vents blow cold air only on the passenger side ( I turn the A/C on ) but no cold air on the driver's side. Presently, I get a low warm current of air from both sides when the blower is turned off. Thanks for any help.

 

sounds like its either hanging up or stuck