Air now comes out of all dash vents after recently fixing a brake booster. Doesn't matter what position it is on, you get air out of all. Shop checked all underhood vacuum lines and none were found bad or cracked or missing. Any help would be appreciated or suggestions. it worked fine before and had the correct distribution of the air throught the vents.

Time to find a new shop

There's a vacuum line that goes from the throttle body, back towards the brake booster, then into a pretty stiff hard plastic line into the dash harness. It feeds to the HVAC panel in the dash. If you remove the dash and pull out the HVAC unit... unclip the vacuum line connector from the back, you should have vacuum on one of the six lines (I believe it's the pink one? But don't quote me on that... it's been years since I had one apart).

If you have no vacuum there, then there's a leak somewhere.

The selector actuator that is controlled by the vacuum can break as well.

My broke 5-6 years ago and was stuck on the defrosters. If you pull the dash pad off you can see the actuator beside the vent on the top of the dash by the windshield. There are a couple of those actuators on the system, one could have a bad line, or be broken.


"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"