As our Reattas get older it is common for the vacuum lines to deteriorate and break. The question often comes up about where to look for vacuum leaks The photos below will help you find the vacuum hoses that need to be inspected. When inspecting the hoses be sure to check the hose that attaches to the vacuum modulator as well.
The small hard plastic vacuum line that runs from the vacuum check valve (photo 3) to the HVAC controller under the dash is prone to breaking. That small plastic line should be checked carefully if you are experiencing air only coming out of the defroster vents on top of the dash.
There is also a large fitting on the intake manifold that was intended to supply vacuum to the brake booster on a Buick Rivera. The fitting is covered with a large rubber cap that should be checked for cracks that could cause it to leak vacuum.
While you are checking the vacuum lines it is a good idea to check the intake manifold for leaks at the same time.