Recently had the heater core replaced in my truck and now i get this air or vacuum leak sound from behind the dash. What i could find searching suggests its the doors on the hvac system. I didn't see anything about the noise changing as you accelerate, as mine does, so im not sure if this is the same problem. AC still works fine, does jump to defrost on steep hills but it's done that forever. If it's not this what else might it be? Also isthis something the shop could have damaged taking the dash out, or back together? Not really looking forward to having to put more money into it...
Thanks for any input.
Thanks for any input.