Close
Q:

what causes the ac vents to change from floor to panel and back by themselves on 2004 Dodge Ram 2500

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
with ac/heater running
(1) Answer
(1) Comments
If vents are controlled by vacuum a loss of vacuum would cause servos to go to a rest position and usually air only comes out of floor and defrost vents. Diesel engines need a vacuum pump because they unlike a gas engine have no or very little vacuum.