Morning Starts

When I start my car in the morning, I hear sounds coming from the

hoses/radiator/heater core, one of the three. I only hear this when the

car has sat all the day and I come to start it up. I wanted to know why

do it make the sound like its sucking something. Can someone help me

out please.

I have the same sound. Appears to be a vacuum actuator behind the dash. Doesn't appear to cause any problems but can be annoying.

That is good, but is it a way that I could replace the part that is making that noise. If so, do you know how?

I'm not aware of any fix.

There is a vacuum canister/valve that holds vacuum pressure for the HVAC mode actuators located under the hood by the A/C accumulator (the silver tank the a/c lines run to) that may be leaking and causing the system to draw vacuum each time your car is started. The GM part number varies according to year and engine.

Cool, so I going to check it out and if that is the problem, I am going to fix it and keep yall informed on if it is still making noise or not