I found the vacuum line right side engine compartment going to the vacuum canister rotted out. I replace the line. I also noticed a smaller plastic vacuum line coming off the vacuum tee disconnected/not going anywhere. I did some research, and it seems to be for the HVAC system. My AC/ heating air controls do not switch from vent to defrost or floor. My question is, where does it go into the firewall? Does it go into the main electrical harness? If so, at what location? I do not see any signs where it would enter the electrical harness. Does anyone have a photo? I really don't want to run a new vacuum line. Thank you in advance.