^^^
No AAV present on 1987 models, bisch, so no buttplug or new hose needed.
The AAR does not react to vacuum - there is a metal disk in there that is moved to the closed position as the heating element inside it warms up - if it is stuck open, that could cause your high idle. Sometimes the disc can be freed up with a little oil. You can actually reach in there with a small screwdriver and gently move it back and forth (
), to see if it moves freely.