The canister purge solenoid on your 1996 Buick Park Avenue should be located on or near the intake manifold. If the under hood emission vacuum hose label is still present it should show the location of the purge solenoid.
RepairPal Certified shops can diagnose and repair your 1996 Buick Park Avenue. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.